Anti-TNFa antibodies and assays employing anti-TNFa antibodies

ABSTRACT

Anti-TNF antibodies and anti-TNF peptides, specific for tumor necrosis factor (TNF) are useful for in vivo diagnosis and therapy of a number of TNF-mediated pathologies and conditions, as well as polynucleotides coding for anti-TNF murine and chimeric antibodies, peptides, methods of making and using the antibody or peptides in immunoassays and immuno-therapeutic approaches are provided, where the anti-TNF peptide is selected from a soluble portion of TNF receptor, an anti-TNF antibody or structural analog thereof.

This application is a continuation-in-part of each of U.S. applicationSer. No. 08/010,406, filed Jan. 29, 1993, now abandoned; and CIP of U.S.application Ser. No. 08/013,413, filed Feb. 2, 1993, now abandoned,which is a continuation-in-part of U.S. application Ser. No. 07/943,852,filed Sep. 11, 1992, now abandoned, which is a continuation-in-part ofU.S. application Ser. No. 07/853,606, filed Mar. 18, 1992, nowabandoned, which is a continuation-in-part of U.S. application Ser. No.07/670,827, filed Mar. 18, 1991, now abandoned. Each of the abovenon-abandoned applications are entirely incorporated herein byreference.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention in the field of immunology and medicine relates toanti-human tumor necrosis factor-alpha (hTNFα) antibodies and peptidesand nucleic acids encoding therefor, and to pharmaceutical anddiagnostic compositions and production, diagnostic and therapeuticmethods thereof, and to methods for treating TNF-mediated pathologies.

2. Description of the Background Art

Tumor Necrosis Factor: Monocytes and macrophages secrete cytokines knownas tumor necrosis factor-α (TNFα) and tumor necrosis factor-β (TNFβ) inresponse to endotoxin or other stimuli. TNFα is a soluble homotrimer of17 kD protein subunits (Smith, et al., J. Biol. Chem. 262:6951-6954(1987)). A membrane-bound 26 kD precursor form of TNF also exists(Kriegler, et al., Cell 53:45-53 (1988)). For reviews of TNF, seeBeutler, et al., Nature 320:584 (1986), Old, Science 230:630 (1986), andLe, et al., Lab. Invest. 56:234 (1987).

Cells other than monocytes or macrophages also make TNFα. For example,human non-monocytic tumor cell lines produce TNF (Rubin, et al., J. Exp.Med. 164:1350 (1986); Spriggs, et al., Proc. Natl. Acad. Sci. USA84:6563 (1987)). CD4⁺ and CD8⁺ peripheral blood T lymphocytes and somecultured T and B cell lines (Cuturi, et al., J. Exp. Med. 165:1581(1987); Sung, et al., J. Exp. Med. 168:1539 (1988)) also produce TNFα.

TNF causes pro-inflammatory actions which result in tissue injury, suchas inducing procoagulant activity on vascular endothelial cells (Pober,et al., J. Immunol. 136:1680 (1986)), increasing the adherence ofneutrophils and lymphocytes (Pober, et al., J. Immunol. 138:3319(1987)), and stimulating the release of platelet activating factor frommacrophages, neutrophils and vascular endothelial cells (Camussi, etal., J. Exp. Med. 166:1390 (1987)).

Recent evidence associates TNF with infections (Cerami, et al., Immunol.Today 9:28 (1988)), immune disorders, neoplastic pathologies (Oliff, etal., Cell 50:555 (1987)), autoimmune pathologies and graft-versus hostpathologies (Piguet, et al., J. Exp. Med. 166:1280 (1987)). Theassociation of TNF with cancer and infectious pathologies is oftenrelated to the host's catabolic state. Cancer patients suffer fromweight loss, usually associated with anorexia.

The extensive wasting which is associated with cancer, and otherdiseases, is known as “cachexia” (Kern, et al. (J. Parent. Enter. Nutr.12:286-298 (1988)). Cachexia includes progressive weight loss, anorexia,and persistent erosion of body mass in response to a malignant growth.The fundamental physiological derangement can relate to a decline infood intake relative to energy expenditure. The cachectic state causesmost cancer morbidity and mortality. TNF can mediate cachexia in cancer,infectious pathology, and other catabolic states.

TNF also plays a central role in gram-negative sepsis and endotoxicshock (Michie, et al., Br. J. Surg. 76:670-671 (1989); Debets, et al.,Second Vienna Shock Forum, p. 463-466 (1989); Simpson, et al., Crit.Care Clin. 5:27-47 (1989)), including fever, malaise, anorexia, andcachexia. Endotoxin strongly activates monocyte/macrophage productionand secretion of TNF and other cytokines (Kornbluth, et al., J. Immunol.137:2585-2591 (1986)). TNF and other monocyte-derived cytokines mediatethe metabolic and neurohormonal responses to endotoxin (Michie, et al.,New. Engl. J. Med. 318:1481-1486 (1988)). Endotoxin administration tohuman volunteers produces acute illness with flu-like symptoms includingfever, tachycardia, increased metabolic rate and stress hormone release(Revhaug, et al., Arch. Surg. 123:162-170 (1988)). Circulating TNFincreases in patients suffering from Gram-negative sepsis (Waage, etal., Lancet 1:355-357 (1987); Hammerle, et al., Second Vienna ShockForum p. 715-718 (1989); Debets, et al., Crit. Care Med. 17:489-497(1989); Calandra, et al., J. Infect. Dis. 161:982-987 (1990)).

TNF Antibodies

Polyclonal murine antibodies to TNF are disclosed by Cerami et al. (EPOPatent Publication 0212489, Mar. 4, 1987). Such antibodies were said tobe useful in diagnostic immunoassays and in therapy of shock inbacterial infections.

Rubin et al. (EPO Patent Publication 0218868, Apr. 22, 1987) disclosesmurine monoclonal antibodies to human TNF, the hybridomas secreting suchantibodies, methods of producing such murine antibodies, and the use ofsuch murine antibodies in immunoassay of TNF.

Yone et al. (EPO Patent Publication 0288088, Oct. 26, 1988) disclosesanti-TNF murine antibodies, including mAbs, and their utility inimmunoassay diagnosis of pathologies, in particular Kawasaki's pathologyand bacterial infection. The body fluids of patients with Kawasaki'spathology (infantile acute febrile mucocutaneous lymph node syndrome;Kawasaki, Allergy 16:178 (1967); Kawasaki, Shonica (Pediatrics) 26:935(1985)) were said to contain elevated TNF levels which were related toprogress of the pathology (Yone et al., infra).

Other investigators have described rodent or murine mAbs specific forrecombinant human TNF which had neutralizing activity in vitro (Liang,et al. (Biochem. Biophys. Res. Comm. 137:847-854 (1986); Meager, et al.,Hybridoma 6:305-311 (1987); Fendly et al., Hybridoma 6:359-369 (1987);Bringman, et al., Hybridoma 6:489-507 (1987); Hirai, et al., J. Immunol.Meth. 96:57-62 (1987); Moller, et al. (Cytokine 2:162-169 (1990)). Someof these mAbs were used to map epitopes of human TNF and develop enzymeimmunoassays (Fendly et al., infra; Hirai et al., infra; Moller et al.,infra) and to assist in the purification of recombinant TNF (Bringman etal., infra). However, these studies do not provide a basis for producingTNF neutralizing antibodies that can be used for in vivo diagnostic ortherapeutic uses in humans, due to immunogenicity, lack of specificityand/or pharmaceutical suitability.

Neutralizing antisera or mAbs to TNF have been shown in mammals otherthan man to abrogate adverse physiological changes and prevent deathafter lethal challenge in experimental endotoxemia and bacteremia. Thiseffect has been demonstrated, e.g., in rodent lethality assays and inprimate pathology model systems (Mathison, et al., J. Clin. Invest.81:1925-1937 (1988); Beutler, et al., Science 229:869-871 (1985);Tracey, et al., Nature 330:662-664 (1987); Shimamoto, et al., Immunol.Lett. 17:311-318 (1988); Silva, et al., J. Infect. Dis. 162:421-427(1990); Opal, et al., J. Infect. Dis. 161:1148-1152 (1990); Hinshaw, etal., Circ. Shock 30:279-292 (1990)).

Putative receptor binding loci of hTNF has been disclosed by Eck andSprang (J. Biol. Chem. 264(29), 17595-17605 (1989), who identified thereceptor binding loci of TNF-α as consisting of amino acids 11-13,37-42, 49-57 and 155-157.

PCT publication WO91/02078 (1991) discloses TNF ligands which can bindto monoclonal antibodies having the following epitopes: at least one of1-20, 56-77, and 108-127; at least two of 1-20, 56-77, 108-127 and138-149; all of 1-18, 58-65, 115-125 and 138-149; all of 1-18, and108-128; all of 56-79, 110-127 and 135- or 136-155; all of 1-30, 117-128and 141-153; all of 1-26, 117-128 and 141-153; all of 22-40, 49-96 or49-97, 110-127 and 136-153; all of 12-22, 36-45, 96-105 and 132-157;both of 1-20 and 76-90; all of 22-40, 69-97, 105-128 and 135-155; all of22-31 and 146-157; all of 22-40 and 49-98; at least one of 22-40, 49-98and 69-97, both of 22-40 and 70-87.

To date, experience with anti-TNF murine mAb therapy in humans has beenlimited. In a phase I study, fourteen patients with severe septic shockwere administered a murine anti-TNF mAb in a single dose from 0.4-10mg/kg (Exley, A. R. et al., Lancet 335:1275-1277 (1990)). However, sevenof the fourteen patients developed a human anti-murine antibody responseto the treatment, which treatment suffers from the known problems due toimmuriogenicity from the use of murine heavy and light chain portions ofthe antibody. Such immunogenicity causes decreased effectiveness ofcontinued administration and can render treatment ineffective, inpatients undergoing diagnostic or therapeutic administration of murineanti-TNF antibodies.

Administration of murine TNF mAb to patients suffering from severe graftversus host pathology has also been reported (Herve, et al., LymphomaRes. 9:591 (1990)).

TNF Receptors

The numerous biological effects of TNFα and the closely relatedcytokine, TNFβ (lymphotoxin), are mediated by two TNF transmembranereceptors, both of which have been cloned. The p55 receptor (also termedTNF-R55, TNF-RI, or TNFRβ) is a 55 kd glycoprotein shown to transducesignals resulting in cytotoxic, anti-viral, and proliferative activitiesof TNFα.

The p75 receptor (also termed TNF-R75, TNF-RII, or TNFRα) is a 75 kDaglycoprotein that has also been shown to transduce cytotoxic andproliferative signals as well as signals resulting in the secretion ofGM-CSF. The extracellular domains of the two receptors have 28% homologyand have in common a set of four subdomains defined by numerousconserved cysteine residues. The p75 receptor differs, however, byhaving a region adjacent to the transmembrane domain that is rich inproline residues and contains sites for O-linked glycosylation.Interestingly, the cytoplasmic domains of the two receptors share noapparent homology which is consistent with observations that they cantransduce different signals to the interior of the cell.

TNFα inhibiting proteins have been detected in normal human urine and inserum of patients with cancer or endotoxemia. These have since beenshown to be the extracellular domains of TNF receptors derived byproteolytic cleavage of the transmembrane forms. Many of the samestimuli that result in TNFα release also result in the release of thesoluble receptors, suggesting that these soluble TNFα inhibitors canserve as part of a negative feedback mechanism to control TNFα activity.

Aderka, et al., Isrl. J. Med. Sci. 28:126-130 (1992) discloses solubleforms of TNF receptors (sTNF-Rs) which specifically bind TNF and thuscan compete with cell surface TNF receptors to bind TNF (Seckinger, etal., J. Exp. Med. 167:1511-1516 (1988); Engelmann, et al., J. Biol.Chem. 264:11974-11980 (1989)).

Loetscher, et al., Cell 61:351-359 (Apr. 20, 1990) discloses the cloningand expression of human 55 kd TNF receptor with the partial amino acidsequence, complete cDNA sequence and predicted amino acid sequence.

Schall et al., Cell 61:361-370 (Apr. 20, 1990), discloses molecularcloning and expression of a receptor for human TNF wherein an isolatedcDNA clone including a receptor as a 415 amino acid protein with anapparent molecular weight of 28 kDa, as well as the cDNA sequence andpredicted amino acid sequence.

Nophar, et al., EMBO J. 9(10):3269-3278 (1990) discloses soluble formsof TNF receptor and that the cDNA for type I TNF-R encodes both the cellsurface and soluble forms of the receptor. The cDNA and predicted aminoacid sequences are disclosed.

Engelmann, et al., J. Biol. Chem. 265(3):1531-1536 (1990), disclosesTNF-binding proteins, purified from human urine, both having anapproximate molecular weight of 30 kDa and binding TNF-α moreeffectively than TNF-β. Sequence data is not disclosed. See alsoEngelmann, et al., J. Biol. Chem. 264(20):11974-11980 (1989).

European Patent publication number 0 433 900 A1, published Jun. 26,1991, owned by YEDA Research and Developemtn Co., Ltd., Wallach, et al.,discloses TNF binding protein I (TBP-I), derivatives and analogsthereof, produced expression of a DNA encoding the entire human type ITNF receptor, or a soluble domain thereof.

PCT publication number WO 92/13095, published Aug. 6, 1992, owned bySynergen, Carmichael et al., discloses methods for treating tumornecrosis factor mediated diseases by administration of a therapeuticallyeffective amount of a TNF inhibitor selected from a 30 kDa TNF inhibitorand a 40 kDa TNF inhibitor selected from the full length 40 kDa TNFinhibitor or modifications thereof.

European Patent Publication number 0 526 905 A2, published Oct. 2, 1993,owned by YEDA Research one Development Company, Ltd., Wallach et al.,discloses multimers of the soluble forms of TNF receptors produced byeither chemical or recombinant methods which are useful for protectingmammals from the diliterious effects of TNF, which include portions ofthe hp55 TNF-receptor.

PCT publication WO 92/07076, published Apr. 30, 1992, owned by CharringCross Sunley Research Center, Feldman et al., discloses modified humanTNFα receptor which consists of the first three cysteine-rich subdomainbut lacks the fourth Cysteine-rich subdomain of the extracellularbinding domain of the 55 kDa or 75 kDa TNF receptor for human TNF α, oran amino acid sequence having a homology of 90% or more with the TNFreceptor sequences.

European Patent Publication 0 412 486 A1, published Feb. 13, 1991, ownedby YEDA Research and Development Co., Ltd., Wallach et al., disclosesantibodies to TNF binding protein I (TBP-I), and fragments thereof,which can be used as diagnostic assays or pharmaceutical agents, eitherinhibiting or mimicking the effects of TNF on cells.

European Patent Publication number 0 398 327 A1, published Nov. 22,1990, owned by YEDA Research and Development Co., Ltd., Wallach et al.,discloses TNF binding protein (TBP) isolated and purified havinginhibitory activity on the cytotoxic effect of TNF, as well as TNFbinding protein II and salts, functional derivatives precursors andactive fractions thereof, as well as polyclonal and monoclonalantibodies to TNF binding protein II.

European Patent Publication 0 308 378 A2, published Mar. 22, 1989, ownedby YEDA Research and Development Co., Ltd., Wallach, et al., disclosesTNF inhibitory protein isolated and substantially purified, havingactivity to inhibit the binding of TNF to TNF receptors and to inhibitthe cytotoxicity of TNF. Additionally disclosed are TNF inhibitoryprotein, salts, functional derivatives and active fractions thereof,used to antagonize the diliterious effects of TNF.

Accordingly, there is a need to provide novel TNF antibodies or peptideswhich overcome the problems of murine antibody immunogenicity and whichprovide reduced immunogenicity and increased neutralization activity.

Citation of documents herein is not intended as an admission that any ofthe documents cited herein is pertinent prior art, or an admission thatthe cited documents is considered material to the patentability of anyof the claims of the present application. All statements as to the dateor representation as to the contents of these documents is based on theinformation available to the applicant and does not constitute anyadmission as to the correctness of the dates or contents of thesedocuments.

SUMMARY OF THE INVENTION

It is object of the present invention to overcome one or moredeficiencies of the background art.

It is also an object of the present invention to provide methods havingutility for in vitro, in situ and/or in vivo diagnosis and/or treatmentof animal cells, tissues or pathologies associated with the presence oftumor necrosis factor (TNF), using anti-TNF antibodies and/or anti-TNFpeptides.

Anti-TNF antibodies (Abs) are intended to include at least one ofmonoclonal rodent-human chimeric antibodies, rodent antibodies, humanantibodies or any portions thereof, having at least one antigen bindingregion of an immunoglobulin variable region, which antibody binds TNF.

Anti-TNF peptides are capable of binding TNF under physiologicalconditions, and can include, but are not limited to, portions of a TNFreceptor and/or portions or structural analogs of anti-TNF antibodyantigen binding regions or variable regions. Such antibodies or peptidesbind TNF with neutralizing and/or inhibiting biological activity.

Anti-TNF antibodies and/or anti-TNF peptides of the present inventioncan be routinely made and/or used according to methods of the presentinvention, such as, but not limited to synthetic methods, hybridomas,and/or recombinant cells expressing nucleic acid encoding such anti-TNFantibodies or peptides.

The present invention also provides antigenic polypeptides of hTNF,corresponding to peptides containing neutralizing epitopes or portionsof TNF that, when such epitopes on TNF are bound by anti-TNF antibodiesor peptides, neutralize or inhibit the biological activity of TNF invitro, in situ or in vivo.

The present invention also provides anti-TNF antibodies and peptides inthe form of pharmaceutical and/or diagnostic compounds and/orcompositions, useful for the diagnostic and/or therapeutic methods ofthe present invention for diagnosing and/or treating TNF-relatedpathologies.

Anti-TNF Abs or anti-TNF peptides of the present invention are providedfor use in diagnostic methods for detecting TNF in patients or animalssuspected of suffering from conditions associated with abnormal TNFproduction, including methods wherein high affinity anti-TNF antibodiesor peptides are contacted with a biological sample from a patient and anantigen-antibody reaction detected. Also included in the presentinvention are kits for detecting TNF in a solution using anti-TNFantibodies or peptides, preferably in detectably labeled form.

The present invention is also directed to an anti-hTNF chimeric antibodycomprising two light chains and two heavy chains, each of the chainscomprising at least part of a human constant region and at least part ofa variable (V) region of non-human origin having specificity to humanTNF, said antibody binding with high affinity to a inhibiting and/orneutralizing epitope of human TNF, such as the antibody cA2. Theinvention is also includes a fragments or a derivative such an antibody,such as one or more portions of the antibody chain, such as the heavychain constant, joining, diversity or variable regions, or the lightchain constant, joining or variable regions.

Methods are also provided for making and using anti-TNF antibodies andpeptides for various utilities of the present invention, such as but notlimited to, hybridoma, recombinant or chemical synthetic methods forproducing anti-TNF antibodies or anti-TNF peptides according to thepresent invention; detecting TNF in a solution or cell; removing TNFfrom a solution or cell, inhibiting one or more biological activities ofTNF in vitro, in situ or in vitro. Such removal can include treatmentmethods of the present invention for alleviating symptoms or pathologiesinvolving TNF, such as, by not limited to bacterial, viral or parasiticinfections, chronic inflammatory diseases, autoimmune diseases,malignancies, and/or neurodegenerative diseases.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a graph showing dose dependent binding of mouse mAb A2 tohuman TNFα.

FIG. 2 is a graph showing lack of recognition of heat-inactivated humanTNFα by mAb A2.

FIG. 3 is a graph showing neutralization of in vitro TNF cytotoxicity bymurine A2. Control: murine IgG1 anti-lipid A mAb (8A1) with naturalhuman TNF. Average absorbance values for controls were as follows: noTNF added=1.08; natural TNF, no antibody=0.290; and recombinant TNF, noantibody=0.500.

FIG. 4 is a graph showing that mAb A2 and chimeric A2 do not inhibit orneutralize human lymphotoxin (TNFβ).

FIG. 5 is a graph showing that mAbs murine A2 and chimeric CA2 do notinhibit or neutralize murine TNFα.

FIGS. 6 and FIG. 7 are graphs showing that mAb A2 inhibits orneutralizes TNF produced by chimpanzee monocytes and rhTNFα.

FIGS. 8A and 8B provides schematic diagrams of the plasmids used forexpression of the chimeric H (pA2HG1apgpt) and L (pA2HuKapgpt) chains ofthe chimeric A2 antibody.

FIGS. 9A and 9B is a graph showing results of a cross-blocking epitopeELISA with murine A2 (mA2) and chimeric (cA2) antibody competitors.

FIGS. 10A and 10B is a graph of a Scatchard analysis of ¹²⁵I-labelledmAb A2 (mA2) and chimeric A2 (cA2) binding to recombinant human TNFαimmobilized on a microtiter plate. Each Ka value was calculated from theaverage of two independent determinations.

FIG. 11 is a graph showing neutralization of TNF cytotoxicity bychimeric A2. The control is a chimeric mouse/human IgG1 anti-plateletmAb (7E3) reacting with natural human TNF. Average absorbance values forcontrols were: no TNF added=1.08; natural TNF, no Ab=0.290; andrecombinant TNF, no Ab=0.500.

FIG. 12 is a graph showing in vitro neutralization of TNF-induced ELAM-1expression by chimeric A2. The control is a chimeric mouse/human IgG1anti-CD4 antibody.

FIG. 13 is an amino acid sequence of human TNF as SEQ ID NO:1.

FIGS. 14A-B FIG. 14A is a graphical representation of epitope mapping ofchimeric mAb cA2 indicating relative binding of cA2 to human TNF peptidepins. FIG. 14B is a graphical representation of epitope mapping ofchimeric mAb cA2 indicating relative binding of cA2 to human TNF peptidepins in the presence of human TNF.

FIG. 15 is an amino acid sequence of human TNF showing sequences havingportions of epitopes recognized by cA2, corresponding to portions ofamino acids 59-80 and/or 87-108 of SEQ ID NO:1.

FIGS. 16A-16B FIG. 16A is a nucleic acid sequence (SEQ ID NO:2) andcorresponding amino acid sequence (SEQ ID NO:3) of a cloned cA2 lightchain variable region. FIG. 16B is a nucleic acid sequence (SEQ ID NO:4)and corresponding amino acid sequence (SEQ ID NO:5) of a cloned cA2heavy chain variable region.

FIG. 17 is a graphical representation of the early morning stiffness forthe five patients in group I, and the four patients in group II isplotted as the mean percent of the baseline value versus time. Bothgroups showed an approximately 80 percent decrease or greater in earlymorning stiffness, which persisted for greater than 40 days.

FIG. 18 is a graphical representation of the assessment of pain using avisual analogue scale for the five patients in group I, and the fourpatients in group II, is plotted as the mean percent of the baselinevalue versus time. Both groups showed an approximately 60 to 80 percentdecrease in pain score which persisted for greater than 40 days.

FIG. 19 is a graphical representation of the Ritchie Articular Index, (ascale scored of joint tenderness), is plotted as the mean percent of thebaseline value versus time. Both groups showed an approximately 80percent decrease in the Ritchie Articular Index, which persisted forgreater than 40 days.

FIG. 20 is a graphical representation of the number of swollen jointsfor the five patients in group I and the four patients in Group II isplotted as the mean percent of baseline value versus time. Both groupsshowed an approximately 70 to 80 percent decrease in swollen joints,which persisted for 30 to 40 days.

FIG. 21 is a graphical representation of the serum C-reactive proteinfor four to five patients in group I, and three of the for patients ingroup II, is plotted as the mean percent of the baseline value versustime. Both groups showed an approximately 80 percent reduction in CRPwhich persisted for 30 to 40 days. The values for patient number 1 andpatient number 7 were omitted from the computations on which the plotsare based, since these patients did not have elevated CRP values atbaseline.

FIG. 22 is a graphical representation of the erythrocyte sedimentationrate for the five patients in group I and three of the patients in groupII is plotted as the mean percent of the baseline value versus time.Both groups showed an approximately 40 percent reduction in ESR whichpersisted for at least 40 days. The data from patient number 9 isomitted from the computations on which the plots were based, since thispatient did not have an elevated ESR at baseline.

FIG. 23 is a graphical representation of the index of Disease Activity,(a composite score of several parameters of disease activity), for thefive patients in group I, and the four patients in group II, is plottedas the mean percent of the baseline value versus time. Both groupsshowed a clinically significant reduction in IDA, which persisted for atleast 40 days.

FIG. 24 is a graphical representation of swollen joint counts (maximum28), as recorded by a single observer. Circles represent individualpatients and horizontal bars show median values at each time point. Thescreening time point was within 4 weeks of entry to the study (week 0);data from patient 15 were not included after week 2 (dropout).Significance of the changes, relative to week 0, by Mann-Whitney test,adjusted: week 1, p>0.05; week 2, p<0.02; weeks 3-4, p<0.002; weeks 6-8,p<0.001.

FIGS. 26A-B is a graphical representation of levels of serum C-reactiveprotein (CRP)-Serum CRP (normal range 0-10 mg/liter), measured bynephelometry. Circles represent individual patients and horizontal barsshow median values at each time point. The screening time point waswithin 4 weeks of entry to the study (week 0); data from patient 15 werenot included after week 2 (dropout). Significance of the changes,relative to week 0, by Mann-Whitney test, adjusted: week 1, p<0.001;week 2, p<0.003; week 3, p<0.002; week 4, p<0.02; week 6,8, p<0.001.FIG. 25B is a schematic illustration of the construction of the vectorsused to express the heavy chain of the immunoreceptors.

FIGS. 26A-B is a schematic illustration of the genes encoding TNFreceptor/IgG fusion proteins and the gene encoding the truncated lightchain. The gene encoding Ig heavy chain (IgH) fusion proteins had thesame basic structure as the naturally occurring, rearranged Ig genesexcept that the Ig variable region coding sequence was replaced with TNFreceptor coding sequence. Except for the TNF receptor coding sequencesand a partial human K sequence derived by modifying the murine J regioncoding sequence in the cM-T412 IgH gene by PCT mutagenesis, the entiregenomic fragment shown originated from the cM-T412 chimeric mouse/humanIgH gene. Looney et al., Hum. Antibody Hybrid. 3:191-200 (1992). Theregion deleted in the genes encoding p55-sf3 and p75P-sf3 is marked inthe figure. The JC_(K) gene, encoding a truncated Ig Kappa light chain,was constructed by deleting the variable region coding sequence from thecM-T412 chimeric mouse/human Ig Kappa gene (Looney, infra) and using PCRmutagenesis to change the murine J sequence to a partial human Jsequence. THe p55-light chain fusion in p55-df2 was made by insertingthe p55 coding sequence into the EcoRV site in the JC_(K) gene. Traceyet al., Nature 330:662-666 (1987). FIG. 26B is a schematic illustrationof several immunoreceptor molecules of the present invention. Theblackened ovals each represent a domain of the IgG1 constant region. THecircles represent the truncated light chain. Small circles adjacent to ap55 or p75 subunit mark the positions of human J sequence. Theincomplete circles in p75-sf2 and -sf3 are to illustrate that theC-terminal 53 amino acids of the p75 extracellular domain were deleted.Lines between subunits represent disulfide bonds.

FIG. 27 is a schematic illustration of the construction of a cM-T412heavy chain so that it has a unique cloning site for insertion offoreign genes such as p55 and p75.

FIG. 28 is a schematic illustration of the construction of the vectorsused to express the heavy chain of the immunoreceptors.

FIG. 29 is a schematic illustration of the construction of a cM-T412light chain so that it has a unique cloning site for insertion offoreign genes such as p55 and p75.

FIG. 30 is a schematic illustration of the construction of the vectorsused to express the light chain of the immunoreceptors.

FIGS. 31A-C shows graphical representations of fusion proteins protectedWEHI 164 cells from TNFβ with actinomycin D and then incubated in 2ng/ml TNFα with varying concentrations of TNFf overnight at 37° C. Cellviability was determined by measuring their uptake of MTT dye. FIG. 31Ashows p55 fusion proteins. FIG. 31B shows p75 fusion proteins. FIG. 31Cshows comparison of the protective ability of the non-fusion form of p55(p55-nf) to p55-sf2.

FIG. 32 is a graphical represation of data showing fusion proteins alsoeffectively protect WEHI 164 cells from TNFβ cytotoxicity.

FIGS. 33A-H are graphical representations of analyses of binding betweenthe various fusion proteins and TNFα by saturation binding (FIGS. 33A-B)and Scatchard analysis (FIGS. 33C-H). A microtiter plate was coated withexcess goat anti-Fc polyclonal antibody and incubated with 10 ng/ml offusion protein in TBST buffer (10 mM Tris-HCl, pH 7.8, 150 mM NaCl,0.05% Tween-20) for 1 hour. Varying amounts of ¹²⁵I labeled TNFα(specific activity—34.8 μCi/μg) was then incubated with the capturedfusion protein in PBS (10 mM Na Phosphate, pH 7.0, 150 mM NaCl) with 1%bovine serum albumin for 2 hours. Unbound TNFα was washed away with fourwashes in PBS and the cpm bound was quantitated using a y-counter. Allsamples were analyzed in triplicate. The slope of the lines in (FIGS.33C-H) represent the affinity constant, K_(a). The dissociation constant(K_(d)) values (see Table I) were derived using the equationK_(d)=1/K_(a).

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Tumor necrosis factor (TNF) has been discovered to mediate or beinvolved in many pathologies, such as, but not limited to bacterial,viral or parasitic infections, chronic inflammatory diseases, autoimmunediseases, malignancies, and/or neurodegenerative diseases. Accordingly,anti-TNF compounds and compositions of the present invention which haveneutralizing and/or inhibiting activity against TNF are discovered toprovide methods for treating and/or diagnosing such pathologies.

The present invention thus provides anti-TNF compounds and compositionscomprising anti-TNF antibodies (Abs) and/or anti-TNF peptides whichinhibit and/or neutralize TNF biological activity in vitro, in situand/or in vivo, as specific for association with neutralizing epitopesof human tumor necrosis factor-alpha (hTNFα) and/or human tumor necrosisfactor β (hTNFβ). Such anti-TNF Abs or peptides have utilities for usein research, diagnostic and/or therapeutic methods of the presentinvention for diagnosing and/or treating animals or humans havingpathologies or conditions associated with the presence of a substancereactive with an anti-TNF antibody, such as TNF or metabolic productsthereof. Such pathologies can include the generalized or local presenceof TNF or related compounds, in amounts and/or concentrations exceeding,or less than, those present in a normal healthy subject, or as relatedto a pathological condition.

Anti-TNF Antibodies and Methods

The term “antibody” is meant to include polyclonal antibodies,monoclonal antibodies (mAbs), chimeric antibodies, anti-idiotypic(anti-Id) antibodies to antibodies that can be labeled in soluble orbound form, as well as fragments, regions or derivatives thereof,provided by any known technique, such as, but not limited to enzymaticcleavage, peptide synthesis or recombinant techniques. Such anti-TNFantibodies of the present invention are capable of binding portions ofTNF that inhibit the binding of TNF to TNF receptors.

Polyclonal antibodies are heterogeneous populations of antibodymolecules derived from the sera of animals immunized with an antigen. Amonoclonal antibody contains a substantially homogeneous population ofantibodies specific to antigens, which population contains substantiallysimilar epitope binding sites. MAbs may be obtained by methods known tothose skilled in the art. See, for example Kohler and Milstein, Nature256:495-497 (1975); U.S. Pat. No. 4,376,110; Ausubel et al, eds.,CURRENT PROTOCOLS IN MOLECULAR BIOLOGY, Greene Publishing Assoc. andWiley Interscience, N.Y., (1987, 1992); and Harlow and Lane ANTIBODIES:A LABORATORY MANUAL Cold Spring Harbor Laboratory (1988); Colligan etal., eds., Current Protocols in Immunology, Greene Publishing Assoc. andWiley Interscience, N.Y., (1992, 1993), the contents of which referencesare incoporated entirely herein by reference. Such antibodies may be ofany immunoglobulin class including IgG, IgM, IgE, IgA, GILD and anysubclass thereof. A hybridoma producing a mAb of the present inventionmay be cultivated in vitro, in situ or in vivo. Production of hightiters of mAbs in vivo or in situ makes this the presently preferredmethod of production.

Chimeric antibodies are molecules different portions of which arederived from different animal species, such as those having variableregion derived from a murine mAb and a human immunoglobulin constantregion, which are primarily used to reduce immunogenicity in applicationand to increase yields in production, for example, where murine mAbshave higher yields from hybridomas but higher immunogenicity in humans,such that human/murine chimeric mAbs are used. Chimeric antibodies andmethods for their production are known in the art (Cabilly et al, Proc.Natl. Acad. Sci. USA 81:3273-3277 (1984); Morrison et al., Proc. Natl.Acad. Sci. USA 81:6851-6855 (1984); Boulianne et al., Nature 312:643-646(1984); Cabilly et al., European Patent Application 125023 (publishedNov. 14, 1984); Neuberger et al., Nature 314:268-270 (1985); Taniguchiet al., European Patent Application 171496 (published Feb. 19, 1985);Morrison et al., European Patent Application 173494 (published Mar. 5,1986); Neuberger et al., PCT Application WO 86/01533, (published Mar.13, 1986); Kudo et al., European Patent Application 184187 (publishedJun. 11, 1986); Morrison et al., European Patent Application 173494(published Mar. 5, 1986); Sahagan et al., J. Immunol. 137:1066-1074(1986); Robinson et al., International Patent Publication#PCT/US86/02269 (published May 7, 1987); Liu et al., Proc. Natl. Acad.Sci. USA 84:3439-3443 (1987); Sun et al., Proc. Natl. Acad. Sci. USA84:214-218 (1987); Better et al., Science 240:1041-1043 (1988); andHarlow and Lane ANTIBODIES: A LABORATORY MANUAL Cold Spring HarborLaboratory (1988)). These references are entirely incorporated herein byreference.

An anti-idiotypic (anti-Id) antibody is an antibody which recognizesunique determinants generally associated with the antigen-binding siteof an antibody. An Id antibody can be prepared by immunizing an animalof the same species and genetic type (e.g., mouse strain) as the sourceof the mAb with the mAb to which an anti-Id is being prepared. Theimmunized animal will recognize and respond to the idiotypicdeterminants of the immunizing antibody by producing an antibody tothese idiotypic determinants (the anti-Id antibody). See, for example,U.S. Pat. No. 4,699,880, which is herein entirely incorporated byreference.

The anti-Id antibody may also be used as an “immunogen” to induce animmune response in yet another animal, producing a so-calledanti-anti-Id antibody. The anti-anti-Id may be epitopically identical tothe original mAb which induced the anti-Id. Thus, by using antibodies tothe idiotypic determinants of a mAb, it is possible to identify otherclones expressing antibodies of identical specificity.

Anti-TNF antibodies of the present invention can include at least one ofa heavy chain constant region (H_(c)), a heavy chain variable region(H_(v)), a light chain variable region (L_(v)) and a light chainconstant regions (L_(c)), wherein a polyclonal Ab, monoclonal Ab,fragment and/or regions thereof include at least one heavy chainvariable region (H_(v)) or light chain variable region (L_(v)) whichbinds a portion of a TNF and inhibits and/or neutralizes at least oneTNF biological activity.

Preferred antibodies of the present invention are high affinityhuman-murine chimeric anti-TNF antibodies, and fragments or regionsthereof, that have potent inhibiting and/or neutralizing activity invivo against human TNFα. Such antibodies and chimeric antibodies caninclude those generated by immunization using purified recombinant hTNFα(SEQ ID NO:1) or peptide fragments thereof. Such fragments can includeepitopes of at least 5 amino acids of residues 87-107, or a combinationof both of 59-80 and 87-108 of hTNFα (as these corresponding amino acidsof SEQ ID NO:1). Additionally, preferred antibodies, fragments andregions of anti-TNF antibodies of the present invention do not recognizeamino acids from at least one of amino acids 11-13, 37-42, 49-57 or155-157 of hTNFα (of SEQ ID NO:1).

Preferred anti-TNF mAbs are also those which will competitively inhibitin vivo the binding to human TNFα of anti-TNFα murine mAb A2, chimericmAb cA2, or an antibody having substantially the same specific bindingcharacteristics, as well as fragments and regions thereof. Preferredantibodies of the present invention are those that bind epitopesrecognized by A2 and cA2, which are included in amino acids 59-80 and/or87-108 of hTNFα (as these corresponding amino acids of SEQ ID NO:1),such that the epitopes consist of at least 5 amino acids which compriseat least one amino acid from the above portions of human TNFα.

Preferred methods for determining mAb specificity and affinity bycompetitive inhibition can be found in Harlow, et al., Antibodies: ALaboratory Manual, Cold Spring Harbor Laboratory Press, Cold SpringHarbor, N.Y., 1988), Colligan et al., eds., Current Protocols inImmunology, Greene Publishing Assoc. and Wiley Interscience, N.Y.,(1992, 1993), and Muller, Meth. Enzymol. 92:589-601 (1983), whichreferences are entirely incorporated herein by reference.

The techniques to raise antibodies of the present invention to smallpeptide sequences that recognize and bind to those sequences in the freeor conjugated form or when presented as a native sequence in the contextof a large protein are well known in the art. Such antibodies includemurine, murine human and human-human antibodies produced by hybridoma orrecombinant techniques known in the art.

As used herein, the term “antigen binding region” refers to that portionof an antibody molecule which contains the amino acid residues thatinteract with an antigen and confer on the antibody its specificity andaffinity for the antigen. The antibody region includes the “framework”amino acid residues necessary to maintain the proper conformation of theantigen-binding residues.

Preferably, the antigen binding region will be of murine origin. Inother embodiments, the antigen binding region can be derived from otheranimal species, in particular rodents such as rabbit, rat or hamster.

The antigen binding region of the chimeric antibody of the presentinvention is preferably derived from a non-human antibody specific forhuman TNF. Preferred sources for the DNA encoding such a non-humanantibody include cell lines which produce antibody, preferably hybridcell lines commonly known as hybridomas. A preferred hybridoma is the A2hybridoma cell line.

An “antigen” is a molecule or a portion of a molecule capable of beingbound by an antibody which is additionally capable of inducing an animalto produce antibody capable of binding to an epitope of that antigen. Anantigen can have one or more than one epitope. The specific reactionreferred to above is meant to indicate that the antigen will react, in ahighly selective manner, with its corresponding antibody and not withthe multitude of other antibodies which can be evoked by other antigens.Preferred antigens that bind antibodies, fragments and regions ofanti-TNF antibodies of the present invention include at least 5 aminoacids comprising at least one of amino acids residues 87-108 or bothresidues 59-80 and 87-108 of hTNFα (of SEQ ID NO:1). Preferred antigensthat bind antibodies, fragments and regions of anti-TNF antibodies ofthe present invention do not include amino acids of amino acids 11-13,37-42, 49-57 or 155-157 of hTNFα (SEQ ID NO:1)

Particular peptides which can be used to generate antibodies of thepresent invention can include combinations of amino acids selected fromat least residues 87-108 or both residues 59-80 and 87-108, which arecombined to provide an epitope of TNF that is bound by anti-TNFantibodies, fragments and regions thereof, and which binding providedanti-TNF biological activity. Such epitopes include at least 1-5 aminoacids and less than 22 amino acids from residues 87-108 or each ofresidues 59-80 and 87-108, which in combination with other amino acidsof TNF provide epitopes of at least 5 amino acids in length.

TNF residues 87-108 or both residues 59-80 and 87-108 of TNF (of SEQ IDNO:1), fragments or combinations of peptides containing therein areuseful as immunogens to raise antibodies that will recognize peptidesequences presented in the context of the native TNF molecule.

The term “epitope” is meant to refer to that portion of any moleculecapable of being recognized by and bound by an antibody at one or moreof the Ab's antigen binding region. Epitopes usually consist ofchemically active surface groupings of molecules such as amino acids orsugar side chains and have specific three dimensional structuralcharacteristics as well as specific charge characteristics. By“inhibiting and/or neutralizing epitope” is intended an epitope, which,when bound by an antibody, results in loss of biological activity of themolecule or organism containing the epitope, in vivo, in vitro or insitu, more preferably in vivo, including binding of TNF to a TNFreceptor.

Epitopes recognized by antibodies, and fragments and regions thereof, ofthe present invention can include 5 or more amino acids comprising atleast one amino acid of each or both of the following amino acidsequences of TNF, which provide a topographical or three dimensionalepitope of TNF which is recognized by, and/or binds with anti-TNFactivity, an antibody, and fragments, and variable regions thereof, ofthe present invention:

59-80:Tyr-Ser-Gln-Val-Leu-Phe-Lys-Gly-Gln-Gly-Cys-Pro-Ser-Thr-His-Val-Leu-Leu-Thr-His-Thr-Ile(AA 59-80 of SEQ ID NO:1); and

87-108: Tyr-Gln-Thr-Lys-Val-Asn-Leu-Leu-Ser-Ala-Ile-Lys-Ser-Pro-Cys-Gln-Arg-Glu-Thr-Pro-Gl u-Gly (AA 87-108 of SEQ IDNO:1).

Preferred antibodies, fragments and regions of anti-TNF antibodies ofthe present invention recognize epitopes including 5 amino acidscomprising at least one amino acid from amino acids residues 87-108 orboth residues 59-80 and 87-108 of hTNFα (of SEQ ID NO:1). Preferredantibodies, fragments and regions of anti-TNF antibodies of the presentinvention do not recognize epitopes from at least one of amino acids11-13, 37-42, 49-57 or 155-157 of hTNFα (of SEQ ID NO:1). In a preferredembodiment, the epitope comprises at least 2 amino acids from residues87-108 or both residues 59-80 and 87-108 of hTNFα (of SEQ ID NO:1). Inanother preferred embodiment, the epitope comprises at least 3 aminoacids from residues 59-80 and 87-108 of hTNFα (of SEQ ID NO:1). Inanother preferred embodiment, the epitope comprises at least 4 aminoacids from residues 87-108 or both residues 59-80 and 87-108 of hTNFα(of SEQ ID NO:1). In another preferred embodiment, the epitope comprisesat least 5 amino acids from residues 87-108 or both residues 59-80 and87-108 of hTNFα (of SEQ ID NO:1). In another preferred embodiment, theepitope comprises at least 6 amino acids from residues 87-108 or bothresidues 59-80 and 87-108 of hTNFα (of SEQ ID NO:1). In anotherpreferred embodiment, the epitope comprises at least 7 amino acids fromresidues 87-108 or both residues 59-80 and 87-108 of hTNFα (of SEQ IDNO:1).

As used herein, the term “chimeric antibody” includes monovalent,divalent or polyvalent immunoglobulins. A monovalent chimeric antibodyis a dimer (HL)) formed by a chimeric H chain associated throughdisulfide bridges with a chimeric L chain. A divalent chimeric antibodyis tetramer (H₂L₂) formed by two HL dimers associated through at leastone disulfide bridge. A polyvalent chimeric antibody can also beproduced, for example, by employing a CH region that aggregates (e.g.,from an IgM H chain, or μ chain).

Murine and chimeric antibodies, fragments and regions of the presentinvention comprise individual heavy (H) and/or light (L) immunoglobulinchains. A chimeric H chain comprises an antigen binding region derivedfrom the H chain of a non-human antibody specific for TNF, which islinked to at least a portion of a human H chain C region (C_(H)), suchas CH₁ or CH₂.

A chimeric L chain according to the present invention, comprises anantigen binding region derived from the L chain of a non-human antibodyspecific for TNF, linked to at least a portion of a human L chain Cregion (C_(L)).

Antibodies, fragments or derivatives having chimeric H chains and Lchains of the same or different variable region binding specificity, canalso be prepared by appropriate association of the individualpolypeptide chains, according to known method steps, e.g., according toAusubel infra, Harlow infra, and Colligan infra, the contents of whichreferences are incoporated entirely herein by reference.

With this approach, hosts expressing chimeric H chains (or theirderivatives) are separately cultured from hosts expressing chimeric Lchains (or their derivatives), and the immunoglobulin chains areseparately recovered and then associated. Alternatively, the hosts canbe co-cultured and the chains allowed to associate spontaneously in theculture medium, followed by recovery of the assembled immunoglobulin,fragment or derivative.

The hybrid cells are formed by the fusion of a non-human anti-hTNFαantibody-producing cell, typically a spleen cell of an animal immunizedagainst either natural or recombinant human TNF, or a peptide fragmentof the human TNFα protein sequence. Alternatively, the non-humananti-TNFα antibody-producing cell can be a B lymphocyte obtained fromthe blood, spleen, lymph nodes or other tissue of an animal immunizedwith TNF.

The second fusion partner, which provides the immortalizing function,can be lymphoblastoid cell or a plasmacytoma or myeloma cell, which isnot itself an antibody producing cell, but is malignant. Preferredfusion partner cells include the hybridoma SP2/0-Ag14, abbreviated asSP2/0 (ATCC CRL1581) and the myeloma P3X63Ag8 (ATCC TIB9), or itsderivatives. See, e.g, Ausubel infra, Harlow infra, and Colligan infra,the contents of which references are incoporated entirely herein byreference.

Murine hybridomas which produce mAb specific for human TNFα or TNFβ areformed by the fusion of a mouse fusion partner cell, such as SP2/0, andspleen cells from mice immunized against purified hTNFα, recombinanthTNFα, natural or synthetic TNF peptides, including peptides including 5or more amino acids selected from residues 59-80, and 87-108 of TNF (ofSEQ ID NO:1) or other biological preparations containing TNF. Toimmunize the mice, a variety of different conventional protocols can befollowed. For example, mice can receive primary and boostingimmunizations of TNF.

The antibody-producing cell contributing the nucleotide sequencesencoding the antigen-binding region of the chimeric antibody of thepresent invention can also be produced by transformation of a non-human,such as a primate, or a human cell. For example, a B lymphocyte whichproduces anti-TNF antibody can be infected and transformed with a virussuch as Epstein-Barr virus to yield an immortal anti-TNF producing cell(Kozbor et al. Immunol. Today 4:72-79 (1983)). Alternatively, the Blymphocyte can be transformed by providing a transforming gene ortransforming gene product, as is well-known in the art. See, e.g,Ausubel infra, Harlow infra, and Colligan infra, the contents of whichreferences are incoporated entirely herein by reference.

Antibody Production Using Hybridomas

The cell fusions are accomplished by standard procedures well known tothose skilled in the field of immunology. Fusion partner cell lines andmethods for fusing and selecting hybridomas and screening for mAbs arewell known in the art. See, e.g, Ausubel infra, Harlow infra, andColligan infra, the contents of which references are incoporatedentirely herein by reference.

The hTNFα-specific murine or chimeric mAb of the present invention canbe produced in large quantities by injecting hybridoma or transfectomacells secreting the antibody into the peritoneal cavity of mice and,after appropriate time, harvesting the ascites fluid which contains ahigh titer of the mAb, and isolating the mAb therefrom. For such in vivoproduction of the mAb with a non-murine hybridoma (e.g., rat or human),hybridoma cells are preferably grown in irradiated or athymic nude mice.Alternatively, the antibodies can be produced by culturing hybridoma ortransfectoma cells in vitro and isolating secreted mAb from the cellculture medium or recombinantly, in eukaryotic or prokaryotic cells.

In a preferred embodiment, the antibody is a MAb which binds amino acidsof an epitope of TNF, which antibody is designated A2, rA2 or cA2, whichis produced by a hybridoma or by a recombinant host. In anotherpreferred embodiment, the antibody is a chimeric antibody whichrecognizes an epitope recognized by A2. In a more preferred embodiment,the antibody is a chimeric antibody designated as chimeric A2 (cA2).

As examples of antibodies according to the present invention, murine mAbA2 of the present invention is produced by a cell line designated c134A.Chimeric antibody cA2 is produced by a cell line designated c168A. Cellline c134A is deposited as a research cell bank in the Centocor CellBiology Services Depository, and cell line c168A(RCB) is deposited as aresearch cell bank in the Centocor Corporate Cell Culture Research andDevelopment Depository, both at Centocor, 200 Great Valley Parkway,Malvern, Pa., 19355. The c168A cell line is also deposited at CentocorBV, Leiden, The Netherlands.

The invention also provides for “derivatives” of the murine or chimericantibodies, fragments, regions or derivatives thereof, which termincludes those proteins encoded by truncated or modified genes to yieldmolecular species functionally resembling the immunoglobulin fragments.The modifications include, but are not limited to, addition of geneticsequences coding for cytotoxic proteins such as plant and bacterialtoxins. The fragments and derivatives can be produced from any of thehosts of this invention. Alternatively, anti-TNF antibodies, fragmentsand regions can be bound to cytotoxic proteins or compounds in vitro, toprovide cytotoxic anti-TNF antibodies which would selectively kill cellshaving TNF receptors.

Fragments include, for example, Fab, Fab′, F(ab′)₂ and Fv. Thesefragments lack the Fc fragment of intact antibody, clear more rapidlyfrom the circulation, and can have less non-specific tissue binding thanan intact antibody (Wahl et al., J. Nucl. Med. 24:316-325 (1983)). Thesefragments are produced from intact antibodies using methods well knownin the art, for example by proteolytic cleavage with enzymes such aspapain (to produce Fab fragments) or pepsin (to produce F(ab′)₂fragments).

The identification of these antigen binding regions and/or epitopesrecognized by mabs of the present invention provides the informationnecessary to generate additional monoclonal antibodies with similarbinding characteristics and therapeutic or diagnostic utility thatparallel the embodiments of this application.

In a preferred embodiment, the amino acids of the epitope are not of atleast one of amino acids 11-13, 37-42, 49-57 and 155-157 of hTNFα (ofSEQ ID NO:1).

Unexpectedly, anti-TNF antibodies or peptides of the present inventioncan block the action of TNF-α without binding to the putative receptorbinding locus such as is presented by Eck and Sprang (J. Biol. Chem.264(29), 17595-17605 (1989), as amino acids 11-13, 37-42, 49-57 and155-157 of hTNFα (of SEQ ID NO:1).

Recombinant Expression of Anti-TNF Antibodies

Recombinant murine or chimeric murine-human or human-human antibodiesthat inhibit TNF and bind an epitope included in the amino acidsequences residues 87-108 or both residues 59-80 and 87-108 of hTNFα (ofSEQ ID NO:1), can be provided according to the present invention usingknown techniques based on the teaching provided herein. See, e.g.,Ausubel et al., eds. Current Protocols in Molecular Biology, WileyInterscience, N.Y. (1987, 1992, 1993); and Sambrook et al. MolecularCloning: A Laboratory Manual, Cold Spring Harbor Laboratory Press(1989), the entire contents of which are incorporated herein byreference.

The DNA encoding an anti-TNF antibody of the present invention can begenomic DNA or cDNA which encodes at least one of the heavy chainconstant region (H_(c)), the heavy chain variable region (H_(v)), thelight chain variable region (L_(v)) and the light chain constant regions(L_(c)). A convenient alternative to the use of chromosomal genefragments as the source of DNA encoding the murine V regionantigen-binding segment is the use of cDNA for the construction ofchimeric immunoglobulin genes, e.g., as reported by Liu et al. (Proc.Natl. Acad. Sci., USA 84:3439 (1987) and J. Immunology 139:3521 (1987),which references are hereby entirely incorporated herein by reference.The use of cDNA requires that gene expression elements appropriate forthe host cell be combined with the gene in order to achieve synthesis ofthe desired protein. The use of cDNA sequences is advantageous overgenomic sequences (which contain introns), in that cDNA sequences can beexpressed in bacteria or other hosts which lack appropriate RNA splicingsystems.

For example, a cDNA encoding a murine V region antigen-binding segmenthaving anti-TNF activity can be provided using known methods based onthe use of the DNA sequence presented in FIG. 16A (SEQ ID NO:2).Alternatively, a cDNA encoding a murine C region antigen-binding segmenthaving anti-TNF activity can be provided using known methods based onthe use of the DNA sequence presented in FIG. 16B (SEQ ID NO:3). Probesthat bind a portion of the DNA sequence presented in FIG. 16A or 16B canbe used to isolate DNA from hybridomas expressing TNF antibodies,fragments or regions, as presented herein, according to the presentinvention, by known methods.

Oligonucleotides representing a portion of the variable region presentedin FIG. 16A or 16B sequence are useful for screening for the presence ofhomologous genes and for the cloning of such genes encoding variable orconstant regions of an anti-TNF antibody. Such probes preferably bind toportions of sequences according to FIG. 17A or 17B which encode lightchain or heavy chain variable regions which bind an activity inhibitingepitope of TNF, especially an epitope of at least 5 amino acids ofresidues 87-108 or a combination of residues 59-80 and 87-108 (of SEQ IDNO:1).

Such techniques for synthesizing such oligonucleotides are well knownand disclosed by, for example, Wu, et al., Prog. Nucl. Acid. Res. Molec.Biol. 21:101-141 (1978)), and Ausubel et al, eds. Current Protocols inMolecular Biology, Wiley Interscience (1987, 1993), the entire contentsof which are herein incorporated by reference.

Because the genetic code is degenerate, more than one codon can be usedto encode a particular amino acid (Watson, et al., infra). Using thegenetic code, one or more different oligonucleotides can be identified,each of which would be capable of encoding the amino acid. Theprobability that a particular oligonucleotide will, in fact, constitutethe actual XXX-encoding sequence can be estimated by consideringabnormal base pairing relationships and the frequency with which aparticular codon is actually used (to encode a particular amino acid) ineukaryotic or prokaryotic cells expressing an anti-TNF antibody orfragment. Such “codon usage rules” are disclosed by Lathe, et al., J.Molec. Biol. 183:1-12 (1985). Using the “codon usage rules” of Lathe, asingle oligonucleotide, or a set of oligonucleotides, that contains atheoretical “most probable” nucleotide sequence capable of encodinganti-TNF variable or constant region sequences is identified.

Although occasionally an amino acid sequence can be encoded by only asingle oligonucleotide, frequently the amino acid sequence can beencoded by any of a set of similar oligonucleotides. Importantly,whereas all of the members of this set contain oligonucleotides whichare capable of encoding the peptide fragment and, thus, potentiallycontain the same oligonucleotide sequence as the gene which encodes thepeptide fragment, only one member of the set contains the nucleotidesequence that is identical to the nucleotide sequence of the gene.Because this member is present within the set, and is capable ofhybridizing to DNA even in the presence of the other members of the set,it is possible to employ the unfractionated set of oligonucleotides inthe same manner in which one would employ a single oligonucleotide toclone the gene that encodes the protein.

The oligonucleotide, or set of oligonucleotides, containing thetheoretical “most probable” sequence capable of encoding an anti-TNFantibody or fragment including a variable or constant region is used toidentify the sequence of a complementary oligonucleotide or set ofoligonucleotides which is capable of hybridizing to the “most probable”sequence, or set of sequences. An oligonucleotide containing such acomplementary sequence can be employed as a probe to identify andisolate the variable or constant region anti-TNF gene (Sambrook et al.,infra).

A suitable oligonucleotide, or set of oligonucleotides, which is capableof encoding a fragment of the variable or constant anti-TNF region (orwhich is complementary to such an oligonucleotide, or set ofoligonucleotides) is identified (using the above-described procedure),synthesized, and hybridized by means well known in the art, against aDNA or, more preferably, a cDNA preparation derived from cells which arecapable of expressing anti-TNF antibodies or variable or constantregions thereof. Single stranded oligonucleotide molecules complementaryto the “most probable” variable or constant anti-TNF region peptidecoding sequences can be synthesized using procedures which are wellknown to those of ordinary skill in the art (Belagaje, et al., J. Biol.Chem. 254:5765-5780 (1979); Maniatis, et al., In: Molecular Mechanismsin the Control of Gene Expression, Nierlich, et al., Eds., Acad. Press,NY (1976); Wu, et al., Prog. Nucl. Acid Res. Molec. Biol. 21:101-141(1978); Khorana, Science 203:614-625 (1979)). Additionally, DNAsynthesis can be achieved through the use of automated synthesizers.Techniques of nucleic acid hybridization are disclosed by Sambrook etal. (infra), and by Haymes, et al. (In: Nucleic Acid Hybridization, APractical Approach, IRL Press, Washington, D.C. (1985)), whichreferences are herein incorporated by reference. Techniques such as, orsimilar to, those described above have successfully enabled the cloningof genes for human aldehyde dehydrogenases (Hsu, et al., Proc. Natl.Acad. Sci. USA 82:3771-3775 (1985)), fibronectin (Suzuki, et al., Eur.Mol. Biol. Organ. J. 4:2519-2524 (1985)), the human estrogen receptorgene (Walter, et al., Proc. Natl. Acad. Sci. USA 82:7889-7893 (1985)),tissue-type plasminogen activator (Pennica, et al., Nature 301:214-221(1983)) and human term placental alkaline phosphatase complementary DNA(Kam, et al., Proc. Natl. Acad. Sci. USA 82:8715-8719 (1985)).

In an alternative way of cloning a polynucleotide encoding an anti-TNFvariable or constant region, a library of expression vectors is preparedby cloning DNA or, more preferably, cDNA (from a cell capable ofexpressing an anti-TNF antibody or variable or constant region) into anexpression vector. The library is then screened for members capable ofexpressing a protein which competitively inhibits the binding of ananti-TNF antibody, such as A2 or cA2, and which has a nucleotidesequence that is capable of encoding polypeptides that have the sameamino acid sequence as anti-TNF antibodies or fragments thereof. In thisembodiment, DNA, or more preferably cDNA, is extracted and purified froma cell which is capable of expressing an anti-TNF antibody or fragment.The purified cDNA is fragmentized (by shearing, endonuclease digestion,etc.) to produce a pool of DNA or cDNA fragments. DNA or cDNA fragmentsfrom this pool are then cloned into an expression vector in order toproduce a genomic library of expression vectors whose members eachcontain a unique cloned DNA or cDNA fragment such as in a lambda phagelibrary, expression in prokaryotic cell (e.g., bacteria) or eukaryoticcells, (e.g., mammalian, yeast, insect or fungus). See, e.g., Ausubel,infra, Harlow, infra, Colligan, infra; Nyyssonen et al. Bio/Technology11:591-595 (Can 1993); Marks et al., Bio/Technology 11:1145-1149(October 1993). Once nucleic acid encoding such variable or constantanti-TNF regions is isolated, the nucleic acid can be appropriatelyexpressed in a host cell, along with other constant or variable heavy orlight chain encoding nucleic acid, in order to provide recombinant MAbsthat bind TNF with inhibitory activity. Such antibodies preferablyinclude a murine or human anti-TNF variable region which contains aframework residue having complimentarily determining residues which areresponsible for antigen binding. In a preferred embodiment, an anti-TNFvariable light or heavy chain encoded by a nucleic acid as describedabove binds an epitope of at least 5 amino acids including residues87-108 or a combination of residues 59-80 and 87-108 of hTNF (of SEQ IDNO:1).

Human genes which encode the constant (C) regions of the murine andchimeric antibodies, fragments and regions of the present invention canbe derived from a human fetal liver library, by known methods. Human Cregions genes can be derived from any human cell including those whichexpress and produce human inmuunoglobulins. The human C_(H) region canbe derived from any of the known classes or isotypes of human H chains,including gamma, μ, α, δ or ε, and subtypes thereof, such as G1, G2, G3and G4. Since the H chain isotype is responsible for the variouseffector functions of an antibody, the choice of C_(H) region will beguided by the desired effector functions, such as complement fixation,or activity in antibody-dependent cellular cytotoxicity (ADCC).Preferably, the C_(H) region is derived from gamma 1 (IgG1), gamma 3(IgG3), gamma 4 (IgG4), or μ (IgM).

The human C_(L) region can be derived from either human L chain isotype,kappa or lambda.

Genes encoding human immunoglobulin C regions are obtained from humancells by standard cloning techniques (Sambrook, et al. (MolecularCloning: A Laboratory Manual, 2nd Edition, Cold Spring Harbor Press,Cold Spring Harbor, N.Y. (1989) and Ausubel et al, eds. CurrentProtocols in Molecular Biology (1987-1993)). Human C region genes arereadily available from known clones containing genes representing thetwo classes of L chains, the five classes of H chains and subclassesthereof. Chimeric antibody fragments, such as F(ab′)₂ and Fab, can beprepared by designing a chimeric H chain gene which is appropriatelytruncated. For example, a chimeric gene encoding an H chain portion ofan F(ab′)₂ fragment would include DNA sequences encoding the CH₁ domainand hinge region of the H chain, followed by a translational stop codonto yield the truncated molecule.

Generally, the murine, human or murine and chimeric antibodies,fragments and regions of the present invention are produced by cloningDNA segments encoding the H and L chain antigen-binding regions of aTNF-specific antibody, and joining these DNA segments to DNA segmentsencoding C_(H) and C_(L) regions, respectively, to produce murine, humanor chimeric immunoglobulin-encoding genes.

Thus, in a preferred embodiment, a fused chimeric gene is created whichcomprises a first DNA segment that encodes at least the antigen-bindingregion of non-human origin, such as a functionally rearranged V regionwith joining (J) segment, linked to a second DNA segment encoding atleast a part of a human C region.

Therefore, cDNA encoding the antibody V and C regions, the method ofproducing the chimeric antibody according to the present inventioninvolves several steps, outlined below:

1. isolation of messenger RNA (mRNA) from the cell line producing ananti-TNF antibody and from optional additional antibodies supplyingheavy and light constant regions; cloning and cDNA production therefrom;

2. preparation of a full length cDNA library from purified mRNA fromwhich the appropriate V and/or C region gene segments of the L and Hchain genes can be: (i) identified with appropriate probes, (ii)sequenced, and (iii) made compatible with a C or V gene segment fromanother antibody for a chimeric antibody;

3. Construction of complete H or L chain coding sequences by linkage ofthe cloned specific V region gene segments to cloned C region gene, asdescribed above;

4. Expression and production of L and H chains in selected hosts,including prokaryotic and eukaryotic cells to provide murine-murine,human-murine, human-human or human murine antibodies.

One common feature of all immunoglobulin H and L chain genes and theirencoded mRNAs is the J region. H and L chain J regions have differentsequences, but a high degree of sequence homology exists (greater than80%) among each group, especially near the C region. This homology isexploited in this method and consensus sequences of H and L chain Jregions can be used to design oligonucleotides for use as primers forintroducing useful restriction sites into the J region for subsequentlinkage of V region segments to human C region segments.

C region cDNA vectors prepared from human cells can be modified bysite-directed mutagenesis to place a restriction site at the analogousposition in the human sequence. For example, one can clone the completehuman kappa chain C (C_(k)) region and the complete human gamma-1 Cregion (C_(gamma-1)). In this case, the alternative method based upongenomic C region clones as the source for C region vectors would notallow these genes to be expressed in bacterial systems where enzymesneeded to remove intervening sequences are absent. Cloned V regionsegments are excised and ligated to L or H chain C region vectors.Alternatively, the human C_(gamma-1) region can be modified byintroducing a termination codon thereby generating a gene sequence whichencodes the H chain portion of an Fab molecule. The coding sequenceswith linked V and C regions are then transferred into appropriateexpression vehicles for expression in appropriate hosts, prokaryotic oreukaryotic.

Two coding DNA sequences are said to be “operably linked” if the linkageresults in a continuously translatable sequence without alteration orinterruption of the triplet reading frame. A DNA coding sequence isoperably linked to a gene expression element if the linkage results inthe proper function of that gene expression element to result inexpression of the coding sequence.

Expression vehicles include plasmids or other vectors. Preferred amongthese are vehicles carrying a functionally complete human C_(H) or C_(L)chain sequence having appropriate restriction sites engineered so thatany V_(H) or V_(L) chain sequence with appropriate cohesive ends can beeasily inserted therein. Human C_(H) or C_(L) chain sequence-containingvehicles thus serve as intermediates for the expression of any desiredcomplete H or L chain in any appropriate host.

A chimeric antibody, such as a mouse-human or human-human, willtypically be synthesized from genes driven by the chromosomal genepromoters native to the mouse H and L chain V regions used in theconstructs; splicing usually occurs between the splice donor site in themouse J region and the splice acceptor site preceding the human C regionand also at the splice regions that occur within the human C_(H) region;polyadenylation and transcription termination occur at nativechromosomal sites downstream of the human coding regions.

Non-Limiting Exemplary Chimeric A2 (cA2) Anti-TNF Antibody of thePresent Invention

Murine MAbs are undesirable for human therapeutic use, due to a shortfree circulating serum half-life and the stimulation of a humananti-murine antibody (HAMA) response. A murine-human chimeric anti-humanTNFα MAb was developed in the present invention with high affinity,epitope specificity and the ability to neutralize the cytotoxic effectsof human TNF. Chimeric A2 anti-TNF consists of the antigen bindingvariable region of the high-affinity neutralizing mouse anti-human TNFIgG1 antibody, designated A2, and the constant regions of a human IgG1,kappa immunoglobulin. The human IgG1 Fc region is expected to: improveallogeneic antibody effector function; increase the circulating serumhalf-life; and decrease the immunogenicity of the antibody. A similarmurine-human chimeric antibody (chimeric 17-1A) has been shown inclinical studies to have a 6-fold longer in vivo circulation time and tobe significantly less immunogenic than its corresponding murine MAbcounterpart (LoBuglio et al., Proc Natl Acad Sci USA 86: 4220-4224,1988).

The avidity and epitope specificity of the chimeric A2 is derived fromthe variable region of the murine A2. In a solid phase ELISA,cross-competition for TNF was observed between chimeric and murine A2,indicating an identical epitope specificity of cA2 and murine A2. Thespecificity of cA2 for TNF-α was confirmed by its inability toneutralize the cytotoxic effects of lymphotoxin(TNF-β). Chimeric A2neutralizes the cytotoxic effect of both natural and recombinant humanTNF in a dose dependent manner. From binding assays of cA2 andrecombinant human TNF, the affinity constant of cA2 was calculated to be1.8×10⁹M⁻¹.

ANTI-TNF Immunoreceptor Peptides

Immunoreceptor peptides of this invention can bind to TNFα and/or TNFβ.The immunoreceptor comprises covalently attached to at least a portionof the TNF receptor at least one immunoglobulin heavy or light chain. Incertain preferred embodiments, the heavy chain constant region comprisesat least a portion of CH₁. Specifically, where a light chain is includedwith an immunoreceptor peptide, the heavy chain must include the area ofCH₁ responsible for binding a light chain constant region.

An immunoreceptor peptide of the present invention can preferablycomprise at least one heavy chain constant region and, in certainembodiments, at least one light chain constant region, with a receptormolecule covalently attached to at least one of the immunoglobulinchains. Light chain or heavy chain variable regions are included incertain embodiments. Since the receptor molecule can be linked withinthe interior of an immunoglobulin chain, a single chain can have avariable region and a fusion to a receptor molecule.

The portion of the TNF receptor linked to the immunoglobulin molecule iscapable of binding TNFα and/or TNFβ. Since the extracellular region ofthe TNF receptor binds TNF, the portion attached to the immunoglobulinmolecule of the immunoreceptor consists of at least a portion of theextracellular region of the TNF receptor. In certain preferredembodiments, the entire extracellular region of p55 is included. Inother preferred embodiments, the entire extracellular region of p75 isincluded. In further preferred embodiments, the extracellular region ofp75 is truncated to delete at least a portion of a region of O-linkedglycosylation and/or a proline-rich region while leaving intact theintramolecular disulfide bridges. Such immunoreceptors comprise at leasta portion of a hinge region wherein at least one heavy chain iscovalently linked to a truncated p75 extracellular region capable ofbinding to TNFα or TNFβ or both. Such a truncated molecule includes, forexample, sequences 1-178, 1-182 or at least 5 amino acid portionsthereof, such as 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19,20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, . .. 50, 60, 70, 80, 90, 100, 110, 120, 130, 140, 150, 160, 170, 180, 190,200, 210, 220, 230, 240, 250, 260, 270, 280, 290 or any value thereon.

Certain embodiments can also include, for example, the C-terminal halfof the hinge region to provide a disulfide bridge between heavy chainswhere both CH₂ and CH₃ chains are present and CH₁ is absent.Alternatively, for example, the N-terminal half of the hinge region canbe included to provide a disulfide bridge with a light chain where onlythe CH₁ region is present.

In certain preferred embodiments of this invention, thenon-immunoglobulin molecule is covalently linked to the N-terminus of atleast one CH₁ region. In other preferred embodiments, thenon-immunoglobulin molecule is covalently linked to an interior sectionof at least one heavy and/or light chain region. Thus, a portion of theTNF receptor can be, for example, at the end of the immunoglobulin chainor in the middle of the chain.

Where the TNF receptor is attached to the middle of the immunoglobulin,the immunoglobulin chain can be truncated, for example, to compensatefor the presence of foreign amino acids, thus resulting in a fusionmolecule of approximately the same length as a natural immunoglobulinchain. Alternatively, for example, the immunoglobulin chain can bepresent substantially in its entirety, thus resulting in a chain that islonger than the corresponding natural immunoglobulin chain.Additionally, the immunoglobulin molecule can be truncated to result ina length intermediate between the size of the entire chain linked to thereceptor molecule and the size of the immunoglobulin chain alone.

In certain preferred embodiments, the heavy chain is an IgG class heavychain. In other preferred embodiments, the heavy chain is an IgM classheavy chain.

In certain preferred embodiments, the heavy chain further comprises atleast about 8 amino acids of a J region.

In certain preferred embodiments, at least a portion of the hinge regionis attached to the CH₁ region. For example, where CH₁ and CH₂ arepresent in the molecule, the entire hinge region is also present toprovide the disulfide bridges between the two heavy chain molecules andbetween the heavy and light chains. Where only CH₁ is present, forexample, the molecule need only contain the portion of the hinge regioncorresponding to the disulfide bridge between the light and heavychains, such as the first 7 amino acids of the hinge.

It will be understood by one skilled in the art, once armed with thepresent disclosure, that the immunoreceptor peptides of the inventioncan be, for example, monomeric or dimeric. For example, the moleculescan have only one light chain and one heavy chain or two light chainsand two heavy chains.

At least one of the non-immunoglobulin molecules linked to animmunoglobin molecule comprises at least a portion of p55 or at least aportion of p75. The portion of the receptor that is included encompassesthe TNF binding site.

In certain preferred embodiments, the non-immunoglobulin moleculecomprises at least 5 amino acid segments of sequences 2-159 of p55. Inother preferred embodiments, the non-immunoglobulin molecule comprisesat least 5 amino acid portions of sequences 1-235 of p75. In furtherpreferred embodiments, the non-immunoglobulin molecule comprises atleast 5 amino acid portions of sequences 1-182 of p75. The above 5 aminoacid portions can be selected from 5, 6, 7, 8, 9, 10, 11, 12, 13, 14,15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32,33, 34, 35, 36, . . . 50, 60, 70, 80, 90, 100, 110, 120, 130, 140, 150,160, 170, 180, 190, 200, 210, 220, 230, 240, 250, 260, 270, 280, 290.

In certain preferred embodiments, each of the two heavy chains and eachof the two light chains is linked to a portion of the TNF receptor, thusforming a tetravalent molecule. Such a tetravalent molecule can have,for example, four p55 receptor molecules; two on the two heavy chainsand two on the two light chains. Alternatively, a tetravalent moleculecan have, for example, a p55 receptor molecule attached to each of thetwo heavy chains and a p75 receptor molecule attached to each of the twolight chains. A tetravalent molecule can also have, for example, p55receptor attached to the light chains and p75 receptor attached to theheavy chains. Additionally, a tetravalent molecule can have one heavychain attached to p55, one heavy chain attached to p75, one light chainattached to p75, and one light chain attached to p55. See, for example,the molecules depicted in FIG. 26A. Further, the molecules can have sixreceptors attached, for example; two within the heavy chains and four atthe ends of the heavy and light chains. Other potential multimers andcombinations would also be within the scope of one skilled in the art,once armed with the present disclosure.

In further preferred embodiments, at least one of the heavy chains has avariable region capable of binding to a second target molecule. Suchmolecules include, for example, CD3, so that one half of a fusionmolecule is a monomeric anti-CD3 antibody.

Additionally, in other embodiments of the present invention, theimmunoreceptor peptides further include an irrelevant variable region onthe light chain and/or heavy chain. Preferably, however, such a regionis absent due to the lowered affinity for TNF which can be present dueto stearic hindrance.

In certain preferred embodiments, the heavy chain is linked to anon-immunoglobulin molecule capable of binding to a second targetmolecule, such as a cytotoxic protein, thus creating a partimmunoreceptor, part immunotoxin that is capable of killing those cellsexpressing TNF. Such cytotoxic proteins, include, but are not limitedto, Ricin-A, Pseudomonas toxin, Diphtheria toxin and TNF. Toxinsconjugated to ligands are known in the art (see, for example, Olsnes, S.et al., Immunol. Today 1989, 10, 291-295). Plant and bacterial toxinstypically kill cells by disruption the protein synthetic machinery.

The Immunoreceptors of this invention can be conjugated to additionaltypes of therapeutic moieties including, but not limited to,radionuclides, cytotoxic agents and drugs. Examples of radionuclidesinclude ²¹²Bi, ¹³¹I, ¹⁸⁶Re, and ⁹⁰Y, which list is not intended to beexhaustive. The radionuclides exert their cytotoxic effect by locallyirradiating the cells, leading to various intracellular lesions, as isknown in the art of radiotherapy.

Cytotoxic drugs which can be conjugated to the immunoreceptors andsubsequently used for in vivo therapy include, but are not limited to,daunorubicin, doxorubicin, methotrexate, and Mitomycin C. Cytotoxicdrugs interfere with critical cellular processes including DNA, RNA, andprotein synthesis. For a fuller exposition of these classes of drugswhich are known in the art, and their mechanisms of action, see Goodman,A. G., et al., Goodman and Gilman's The Pharmacological Basis ofTherapeutics, 8th Ed., Macmillan Publishing Col, 1990. Katzung, ed.,Basic and Clinical Pharmacology, Fifth Edition, p 768-769, 808-809, 896,Appleton and Lange, Norwalk, Conn.

In preferred embodiments, immunoreceptor molecules of the invention arecapable of binding with high affinity to a neutralizing epitope of humanTNFα or TNFβ in vivo. Preferably, the binding affinity is at least about1.6×10¹⁰ M-1. See, for example, Table 1 below. Additionally, inpreferred embodiments, immunoreceptor molecules of the invention arecapable of neutralizing TNF at an efficiency of about a concentration ofless than 130 pM to neutralize 39.2 pM human TNFα. See, for example,Table 1.

TABLE 1 Summary of affinities of different fusion proteins for TNFαMolar ration fp: TNFα at protein IC₅₀* IC₅₀ K_(D) (pM) p55-sf2    70 1.857 p55-df2    55 1.4 60 p55-sf3   100 2.6 48 p55-nf 36,000 900 n.d.p75-sf2   130 3.3 33 p75P-sf2    70 1.8 29 p75P-sf3   130 3.3 15 *IC₅₀ =concentration of fusion protein required to inhibit 2 ng/ml (39.2 pM)TNFα by 50% .62

Once armed with the present disclosure, one skilled in the art would beable to create fragments of the immunoreceptor peptides of theinvention. Such fragments are intended to be within the scope of thisinvention. For example, once the molecules are isolated, they can becleaved with protease to generate fragments that remain capable ofbinding TNF.

Once armed with the present disclosure, one skilled in the art wouldalso be able to create derivatives of the immunoreceptor peptides of theinvention. Such derivatives are intended to be within the scope of thisinvention. For example, amino acids in the immunoreceptor thatconstitute a protease recognition site can be modified to avoid proteasecleavage and thus confer greater stability, such as KEX2 sites.

One skilled in the art, once armed with the present disclosure, would beable to synthesize the molecules of the invention. The immunoreceptorpeptides can be constructed, for example, by vector-mediated synthesis,as described in Example XXIV. In general, two expression vectors arepreferably used; one for the heavy chain, one for the light chain. Avector for expression an immunoglobulin preferably consists of apromoter linked to the signal sequence, followed by the constant region.The vector additionally preferably contains a gene providing for theselection of transfected cells expressing the construct. In certainpreferred embodiments, sequences derived from the J region are alsoincluded.

The immunoglobulin gene can be from any vertebrate source, such asmurine, but preferably, it encodes an immunoglobulin having asubstantial number of sequences that are of the same origin as theeventual recipient of the immunoreceptor peptide. For example, if ahuman is treated with a molecule of the invention, preferably theimmunoglobulin is of human origin.

TNF receptor constructs for linking to the heavy chain can besynthesized, for example, using DNA encoding amino acids present in thecellular domain of the receptor. Putative receptor binding loci of hTNFhave been presented by Eck and Sprange, J. Biol. Chem. 1989, 264(29),17595-17605, who identified the receptor binding loci of TNF-α asconsisting of amino acids 11-13, 37-42, 49-57 and 155-157. PCTapplication WO91/02078 (priority date of Aug. 7, 1989) discloses TNFligands which can bind to monoclonal antibodies having the followingepitopes of at least one of 1-20, 56-77, and 108-127; at least two of1-20, 56-77, 108-127 and 138-149; all of 1-18, 58-65, 115-125 and138-149; all of 1-18, and 108-128; all of 56-79, 110-127 and 135- or136-155; all of 1-30, 117-128 and 141-153; all of 1-26, 117-128 and141-153; all of 22-40, 49-96 or -97, 110-127 and 136-153; all of 12-22,36-45, 96-105 and 132-157; all of both of 1-20 and 76-90; all of 22-40,69-97, 105-128 and 135-155; all of 22-31 and 146-157; all of 22-40 and49-98; at least one of 22-40, 49-98 and 69-97, both of 22-40 and 70-87.Thus, one skilled in the art, once armed with the present disclosure,would be able to create TNF receptor fusion proteins using portions ofthe receptor that are known to bind TNF.

Advantages of using an immunoglobulin fusion protein (immunoreceptorpeptide) of the present invention include one or more of (1) possibleincreased avidity for multivalent ligands due to the resulting bivalencyof dimeric fusion proteins, (2) longer serum half-life, (3) the abilityto activate effector cells via the Fc domain, (4) ease of purification(for example, by protein A chromatography), (5) affinity for TNFα andTNFβ and (6) the ability to block TNFα or TNFβ cytotoxicity.

TNF receptor/IgG fusion proteins have shown greater affinity for TNF αin vitro than their monovalent, non-fusion counterparts. These types offusion proteins, which also bind murine TNF with high affinity, havealso been shown to protect mice from lipopolysaccharide-inducedendotoxemia. Lesslauer et al., Eur. J. Immunol. 1991, 21, 2883-2886; andAshkenazi et al., Proc. Natl. Acad. Sci. USA 1991, 88, 10535-10539.Unlike the molecules of the present invention, the TNF receptor/IgGfusion proteins reported to date have had the receptor sequence fuseddirectly to the hinge domain of IgGs such that the first constant domain(CH₁) of the heavy chain was omitted. Lesslauer et al., Eur. J. Immunol.1991, 21, 2883-2886; Ashkenzi et al., Proc. Natl. Acad. Sci. USA 1991,88, 10535-10539; and Peppel et al., J. Exp. Med. 1991, 174, 1483-1489.

While this generally permits secretion of the fusion protein in theabsence of an Ig light chain, a major embodiment of the presentinvention provides for the inclusion of the CH₁ domain, which can conferadvantages such as (1) increased distance and/or flexibility between tworeceptor molecules resulting in greater affinity for TNF, (2) theability to create a heavy chain fusion protein and a light chain fusionprotein that would assemble with each other and dimerize to form atetravalent (double fusion) receptor molecule, and (3) a tetravalentfusion protein can have increased affinity and/or neutralizingcapability for TNF compared to a bivalent (single fusion) molecule.

Unlike other TNF receptor/IgG fusion proteins that have been reported,the fusion proteins of a major embodiment of the present inventioninclude the first constant domain (CH₁) of the heavy chain. The CH₁domain is largely responsible for interactions with light chains. Thelight chain, in turn, provides a vehicle for attaching a second set ofTNF receptor molecules to the immunoreceptor peptide.

It was discovered using the molecules of the present invention that thep55/light chain fusion proteins and p55/heavy chain fusion proteinswould assemble with each other and dimerize to form an antibody-likemolecule that is tetravalent with respect to p55. The resultingtetravalent p55 molecules can confer more protection against, and havegreater affinity for, TNFα or TNFβ than the bivalent p55 molecules.Despite the presumed close proximity of the two light chain p55 domainsto the heavy chain p55 domains, they do not appear to stereocilia hinderor reduce the affinity for TNF.

Inclusion of the CH₁ domain also meant that secretion of the fusionprotein was likely to be inefficient in the absence of light chain. Thishas been shown to be due to a ubiquitous immunoglobulin binding protein(BiP) that binds to the C_(H)1 domain of heavy chains that are notassembled with a light chain and sequesters them in the endoplasmicreticulum. Karlsson et al., J. Immunol. Methods 1991, 145, 229-240.

In initial experiments, an irrelevant light chain was co-transfectedwith the p55-heavy chain construct and subsequent analyses showed thatthe two chains did assemble and that the resulting fusion proteinprotected WEHI cells from TNFα. However, it was considered likely thatthe variable region of the irrelevant light chain would stereociliahinder interactions between the p55 subunits and TNFα. For this reason,a mouse-human chimeric antibody light chain gene was engineered by (1)deleting the variable region coding sequence, and (2) replacing themurine J coding sequence with human J coding sequence. Use of thistruncated light chain, which was shown to assemble and disulfide bondwith heavy chains, increased the efficiency of TNF inhibition byapproximately 30-fold compared to use of a complete irrelevant lightchain.

Comparison of the abilities of p75-sf2 and p75P-sf2 to inhibit TNFcytotoxicity indicated that the C-terminal 53 amino acids of theextracellular domain of p75, which defines a region that is rich inproline residues and contains the only sites of O-linked glycosylation,are not necessary for high-affinity binding to TNFα or TNFβ. In fact,the p75P-sf2 construct repeatedly showed higher affinity binding to TNFβthan p75-sf2. Surprisingly, there was no difference observed between thetwo constructs in their affinity for TNFα.

It is possible that a cell-surface version of p75-P would also bind TNFβwith higher affinity than the complete p75 extracellular domain. Asimilar region is found adjacent to the transmembrane domain in the lowaffinity nerve growth factor receptor whose extracellular domain showsthe same degree of similarity to p75 as p55 does. Mallett et al.,Immunol. Today 1991, 12, 220-223.

Two groups have reported that in cell cytotoxicity assays, their p55fusion protein could be present at a 3-fold (Lesslauer et al., Eur. J.Immunol. 1991, 21, 2883-2886) or 6-8 fold (Ashkenazi et al., Proc. Natl.Acad. Sci. USA 1991, 88, 10535-10539) lower concentration than theirmonovalent p55 and still get the same degree of protection, whileanother group (Peppel et al., J. Exp. Med. 1991, 174, 1483-1489) showedthat their p55 fusion protein could be present at a 1000-fold lowerconcentration than monomeric p55. Thus, the prior art has shownunpredictability in the great variability in the efficiency of differentfusion proteins.

The molecules of the present invention have demonstrated the same degreeof protection against TNF in a 5000-fold lower molar concentration thanmonomeric p55. (See Table 1.) It is believed that the presence of theCH₁ chain in the molecules of a major embodiment of the presentinvention can confer greater flexibility to the molecule and avoidstearic hindrance with the binding of the TNF receptor.

Recombinant Expression of Anti-TNF Antibodies and Anti-TNF Peptides.

A nucleic acid sequence encoding at least one anti-TNF peptide or Abfragment of the present invention may be recombined with vector DNA inaccordance with conventional techniques, including blunt-ended orstaggered-ended termini for ligation, restriction enzyme digestion toprovide appropriate termini, filling in of cohesive ends as appropriate,alkaline phosphatase treatment to avoid undesirable joining, andligation with appropriate ligases. Techniques for such manipulations aredisclosed, e.g., by Ausubel, infra, Sambrook, infra, entirelyincorporated herein by reference, and are well known in the art.

A nucleic acid molecule, such as DNA, is said to be “capable ofexpressing” a polypeptide if it contains nucleotide sequences whichcontain transcriptional and translational regulatory information andsuch sequences are “operably linked” to nucleotide sequences whichencode the polypeptide. An operable linkage is a linkage in which theregulatory DNA sequences and the DNA sequence sought to be expressed areconnected in such a way as to permit gene expression as anti-TNFpeptides or Ab fragments in recoverable amounts. The precise nature ofthe regulatory regions needed for gene expression may vary from organismto organism, as is well known in the analogous art. See, e.g., Sambrook,supra and Ausubel supra.

The present invention accordingly encompasses the expression of ananti-TNF peptide or Ab fragment, in either prokaryotic or eukaryoticcells, although eukaryotic expression is preferred.

Preferred hosts are bacterial or eukaryotic hosts including bacteria,yeast, insects, fungi, bird and mammalian cells either in vivo, or insitu, or host cells of mammalian, insect, bird or yeast origin. It ispreferred that the mammalian cell or tissue is of human, primate,hamster, rabbit, rodent, cow, pig, sheep, horse, goat, dog or catorigin, but any other mammalian cell may be used.

Further, by use of, for example, the yeast ubiquitin hydrolase system,in vivo synthesis of ubiquitin-transmembrane polypeptide fusion proteinsmay be accomplished. The fusion proteins so produced may be processed invivo or purified and processed in vitro, allowing synthesis of ananti-TNF peptide or Ab fragment of the present invention with aspecified amino terminus sequence. Moreover, problems associated withretention of initiation codon-derived methionine residues in directyeast (or bacterial) expression may be avoided. Sabin et al.,Bio/Technol. 7(7): 705-709 (1989); Miller et al., Bio/Technol. 7(7):698-704 (1989).

Any of a series of yeast gene expression systems incorporating promoterand termination elements from the actively expressed genes coding forglycolytic enzymes produced in large quantities when yeast are grown inmediums rich in glucose can be utilized to obtain anti-TNF peptides orAb fragments of the present invention. Known glycolytic genes can alsoprovide very efficient transcriptional control signals. For example, thepromoter and terminator signals of the phosphoglycerate kinase gene canbe utilized.

Production of anti-TNF peptides or Ab fragments or functionalderivatives thereof in insects can be achieved, for example, byinfecting the insect host with a baculovirus engineered to expresstransmembrane polypeptide by methods known to those of skill. SeeAusubel et al, eds. Current Protocols in Molecular Biology, WileyInterscience, §§16.8-16.11 (1987, 1993).

In a preferred embodiment, the introduced nucleotide sequence will beincorporated into a plasmid or viral vector capable of autonomousreplication in the recipient host. Any of a wide variety of vectors maybe employed for this purpose. See, e.g., Ausubel et al, infra, §§ 1.5,1.10, 7.1, 7.3, 8.1, 9.6, 9.7, 13.4, 16.2, 16.6, and 16.8-16.11. Factorsof importance in selecting a particular plasmid or viral vector include:the ease with which recipient cells that contain the vector may berecognized and selected from those recipient cells which do not containthe vector; the number of copies of the vector which are desired in aparticular host; and whether it is desirable to be able to “shuttle” thevector between host cells of different species.

Preferred prokaryotic vectors known in the art include plasmids such asthose capable of replication in E. coli (such as, for example, pBR322,ColE1, pSC101, pACYC 184, πVX). Such plasmids are, for example,disclosed by Maniatis, T., et al. (Molecular Cloning, A LaboratoryManual, Second Edition, Cold Spring Harbor Press, Cold Spring Harbor,N.Y. (1989); Ausubel, infra. Bacillus plasmids include pC194, pC221,pT127, etc. Such plasmids are disclosed by Gryczan, T. (In: TheMolecular Biology of the Bacilli, Academic Press, NY (1982), pp.307-329). Suitable Streptomyces plasmids include pIJ101 (Kendall, K. J.,et al., J. Bacteriol. 169:4177-4183 (1987)), and streptomycesbacteriophages such as φC31 (Chater, K. F., et al., In: SixthInternational Symposium on Actinomycetales Biology, Akademiai Kaido,Budapest, Hungary (1986), pp. 45-54). Pseudomonas plasmids are reviewedby John, J. F., et al. (Rev. Infect. Dis. 8:693-704 (1986)), and Izaki,K. (Jpn. J. Bacteriol. 33:729-742 (1978); and Ausubel et al, supra).

Alternatively, gene expression elements useful for the expression ofcDNA encoding anti-TNF antibodies or peptides include, but are notlimited to (a) viral transcription promoters and their enhancerelements, such as the SV40 early promoter (Okayama, et al., Mol. Cell.Biol. 3:280 (1983)), Rous sarcoma virus LTR (Gorman, et al., Proc. Natl.Acad. Sci., USA 79:6777 (1982)), and Moloney murine leukemia virus LTR(Grosschedl, et al., Cell 41:885 (1985)); (b) splice regions andpolyadenylation sites such as those derived from the SV40 late region(Okayama et al., infra); and (c) polyadenylation sites such as in SV40(Okayama et al., infra).

Immunoglobulin cDNA genes can be expressed as described by Liu et al.,infra, and Weidle et al., Gene 51:21 (1987), using as expressionelements the SV40 early promoter and its enhancer, the mouseimmunoglobulin H chain promoter enhancers, SV40 late region mRNAsplicing, rabbit β-globin intervening sequence, immunoglobulin andrabbit β-globin polyadenylation sites, and SV40 polyadenylationelements. For immunoglobulin genes comprised of part cDNA, part genomicDNA (Whittle et al., Protein Engineering 1:499 (1987)), thetranscriptional promoter is human cytomegalovirus, the promoterenhancers are cytomegalovirus and mouse/human immunoglobulin, and mRNAsplicing and polyadenylation regions are from the native chromosomalimmunoglobulin sequences.

In one embodiment, for expression of cDNA genes in rodent cells, thetranscriptional promoter is a viral LTR sequence, the transcriptionalpromoter enhancers are either or both the mouse immunoglobulin heavychain enhancer and the viral LTR enhancer, the splice region contains anintron of greater than 31 bp, and the polyadenylation and transcriptiontermination regions are derived from the native chromosomal sequencecorresponding to the immunoglobulin chain being synthesized. In otherembodiments, cDNA sequences encoding other proteins are combined withthe above-recited expression elements to achieve expression of theproteins in mammalian cells.

Each fused gene is assembled in, or inserted into, an expression vector.Recipient cells capable of expressing the chimeric immunoglobulin chaingene product are then transfected singly with an anti-TNF peptide orchimeric H or chimeric L chain-encoding gene, or are co-transfected witha chimeric H and a chimeric L chain gene. The transfected recipientcells are cultured under conditions that permit expression of theincorporated genes and the expressed immunoglobulin chains or intactantibodies or fragments are recovered from the culture.

In one embodiment, the fused genes encoding the anti-TNF peptide orchimeric H and L chains, or portions thereof, are assembled in separateexpression vectors that are then used to co-transfect a recipient cell.

Each vector can contain two selectable genes, a first selectable genedesigned for selection in a bacterial system and a second selectablegene designed for selection in a eukaryotic system, wherein each vectorhas a different pair of genes. This strategy results in vectors whichfirst direct the production, and permit amplification, of the fusedgenes in a bacterial system. The genes so produced and amplified in abacterial host are subsequently used to co-transfect a eukaryotic cell,and allow selection of a co-transfected cell carrying the desiredtransfected genes.

Examples of selectable genes for use in a bacterial system are the genethat confers resistance to ampicillin and the gene that confersresistance to chloramphenicol. Preferred selectable genes for use ineukaryotic transfectants include the xanthine guanine phosphoribosyltransferase gene (designated gpt) and the phosphotransferase gene fromTn5 (designated neo).

Selection of cells expressing gpt is based on the fact that the enzymeencoded by this gene utilizes xanthine as a substrate for purinenucleotide synthesis, whereas the analogous endogenous enzyme cannot. Ina medium containing (1) mycophenolic acid, which blocks the conversionof inosine monophosphate to xanthine monophosphate, and (2) xanthine,only cells expressing the gpt gene can survive. The product of the neoblocks the inhibition of protein synthesis by the antibiotic G418 andother antibiotics of the neomycin class.

The two selection procedures can be used simultaneously or sequentiallyto select for the expression of immunoglobulin chain genes introduced ontwo different DNA vectors into a eukaryotic cell. It is not necessary toinclude different selectable markers for eukaryotic cells; an H and an Lchain vector, each containing the same selectable marker can beco-transfected. After selection of the appropriately resistant cells,the majority of the clones will contain integrated copies of both H andL chain vectors and/or anti-TNF peptides.

Alternatively, the fused genes encoding the chimeric H and L chains canbe assembled on the same expression vector.

For transfection of the expression vectors and production of thechimeric antibody, the preferred recipient cell line is a myeloma cell.Myeloma cells can synthesize, assemble and secrete immunoglobulinsencoded by transfected immunoglobulin genes and possess the mechanismfor glycosylation of the immunoglobulin. A particularly preferredrecipient cell is the recombinant Ig-producing myeloma cell SP2/0 (ATCC#CRL 8287). SP2/0 cells produce only immunoglobulin encoded by thetransfected genes. Myeloma cells can be grown in culture or in theperitoneal cavity of a mouse, where secreted immunoglobulin can beobtained from ascites fluid. Other suitable recipient cells includelymphoid cells such as B lymphocytes of human or non-human origin,hybridoma cells of human or non-human origin, or interspeciesheterohybridoma cells.

The expression vector carrying a chimeric antibody construct or anti-TNFpeptide of the present invention can be introduced into an appropriatehost cell by any of a variety of suitable means, including suchbiochemical means as transformation, transfection, conjugation,protoplast fusion, calcium phosphate-precipitation, and application withpolycations such as diethylaminoethyl (DEAE) dextran, and suchmechanical means as electroporation, direct microinjection, andmicroprojectile bombardment (Johnston et al., Science 240:1538 (1988)).A preferred way of introducing DNA into lymphoid cells is byelectroporation (Potter et al., Proc. Natl. Acad. Sci. USA 81:7161(1984); Yoshikawa, et al., Jpn. J. Cancer Res. 77:1122-1133). In thisprocedure, recipient cells are subjected to an electric pulse in thepresence of the DNA to be incorporated. Typically, after transfection,cells are allowed to recover in complete medium for about 24 hours, andare then seeded in 96-well culture plates in the presence of theselective medium. G418 selection is performed using about 0.4 to 0.8mg/ml G418. Mycophenolic acid selection utilizes about 6 μg/ml plusabout 0.25 mg/ml xanthine. The electroporation technique is expected toyield transfection frequencies of about 10⁻⁵ to about 10⁻⁴ for Sp2/0cells. In the protoplast fusion method, lysozyme is used to strip cellwalls from catarrhal harboring the recombinant plasmid containing thechimeric antibody gene. The resulting spheroplasts are fused withmyeloma cells with polyethylene glycol.

The immunoglobulin genes of the present invention can also be expressedin nonlymphoid mammalian cells or in other eukaryotic cells, such asyeast, or in prokaryotic cells, in particular bacteria.

Yeast provides substantial advantages over bacteria for the productionof immunoglobulin H and L chains. Yeasts carry out post-translationalpeptide modifications including glycosylation. A number of recombinantDNA strategies now exist which utilize strong promoter sequences andhigh copy number plasmids which can be used for production of thedesired proteins in yeast. Yeast recognizes leader sequences of clonedmaamalian gene products and secretes peptides bearing leader sequences(i.e., pre-peptides) (Hitzman, et al., 11th International Conference onYeast, Genetics and Molecular Biology, Montpelier, France, Sep. 13-17,1982).

Yeast gene expression systems can be routinely evaluated for the levelsof production, secretion and the stability of anti-TNF peptides,antibody and assembled murine and chimeric antibodies, fragments andregions thereof. Any of a series of yeast gene expression systemsincorporating promoter and termination elements from the activelyexpressed genes coding for glycolytic enzymes produced in largequantities when yeasts are grown in media rich in glucose can beutilized. Known glycolytic genes can also provide very efficienttranscription control signals. For example, the promoter and terminatorsignals of the phosphoglycerate kinase (PGK) gene can be utilized. Anumber of approaches can be taken for evaluating optimal expressionplasmids for the expression of cloned immunoglobulin cDNAs in yeast (seeGlover, ed., DNA Cloning, Vol. II, pp45-66, IRL Press, 1985).

Bacterial strains can also be utilized as hosts for the production ofantibody molecules or peptides described by this invention, E. coli K12strains such as E. coli W3110 (ATCC 27325), and other enterobacteriasuch as Salmonella typhimurium or Serratia marcescens, and variousPseudomonas species can be used.

Plasmid vectors containing replicon and control sequences which arederived from species compatible with a host cell are used in connectionwith these bacterial hosts. The vector carries a replication site, aswell as specific genes which are capable of providing phenotypicselection in transformed cells. A number of approaches can be taken forevaluating the expression plasmids for the production of murine andchimeric antibodies, fragments and regions or antibody chains encoded bythe cloned immunoglobulin cDNAs in bacteria (see Glover, ed., DNACloning, Vol. I, IRL Press, 1985, Ausubel, infra, Sambrook, infra,Colligan, infra).

Preferred hosts are mammalian cells, grown in vitro or in vivo.Mammalian cells provide post-translational modifications toimmunoglobulin protein molecules including leader peptide removal,folding and assembly of H and L chains, glycosylation of the antibodymolecules, and secretion of functional antibody protein.

Mammalian cells which can be useful as hosts for the production ofantibody proteins, in addition to the cells of lymphoid origin describedabove, include cells of fibroblast origin, such as Vero (ATCC CRL 81) orCHO-K1 (ATCC CRL 61).

Many vector systems are available for the expression of cloned anti TNFpeptides H and L chain genes in mammalian cells (see Glover, ed., DNACloning, Vol. II, pp143-238, IRL Press, 1985). Different approaches canbe followed to obtain complete H₂L₂ antibodies. As discussed above, itis possible to co-express H and L chains in the same cells to achieveintracellular association and linkage of H and L chains into completetetrameric H₂L₂ antibodies and/or anti-TNF peptides. The co-expressioncan occur by using either the same or different plasmids in the samehost. Genes for both H and L chains and/or anti-TNF peptides can beplaced into the same plasmid, which is then transfected into cells,thereby selecting directly for cells that express both chains.Alternatively, cells can be transfected first with a plasmid encodingone chain, for example the L chain, followed by transfection of theresulting cell line with an H chain plasmid containing a secondselectable marker. Cell lines producing anti-TNF peptides and/or H₂L₂molecules via either route could be transfected with plasmids encodingadditional copies of peptides, H, L, or H plus L chains in conjunctionwith additional selectable markers to generate cell lines with enhancedproperties, such as higher production of assembled H₂L₂ antibodymolecules or enhanced stability of the transfected cell lines.

Anti-idiotype Abs. In addition to monoclonal or chimeric anti-TNFantibodies, the present invention is also directed to an anti-idiotypic(anti-Id) antibody specific for the anti-TNF antibody of the invention.An anti-Id antibody is an antibody which recognizes unique determinantsgenerally associated with the antigen-binding region of anotherantibody. The antibody specific for TNF is termed the idiotypic or Idantibody. The anti-Id can be prepared by immunizing an animal of thesame species and genetic type (e.g. mouse strain) as the source of theId antibody with the Id antibody or the antigen-binding region thereof.The immunized animal will recognize and respond to the idiotypicdeterminants of the immunizing antibody and produce an anti-Id antibody.The anti-Id antibody can also be used as an “immunogen” to induce animmune response in yet another animal, producing a so-calledanti-anti-Id antibody. The anti-anti-Id can be epitopically identical tothe original antibody which induced the anti-Id. Thus, by usingantibodies to the idiotypic determinants of a mAb, it is possible toidentify other clones expressing antibodies of identical specificity.

Accordingly, mAbs generated against TNF according to the presentinvention can be used to induce anti-Id antibodies in suitable animals,such as BALB/c mice. Spleen cells from such immunized mice can be usedto produce anti-Id hybridomas secreting anti-Id mAbs. Further, theanti-Id mAbs can be coupled to a carrier such as keyhole limpethemocyanin (KLH) and used to immunize additional BALB/c mice. Sera fromthese mice will contain anti-anti-Id antibodies that have the bindingproperties of the original mAb specific for a TNF epitope.

Screening Methods for determining tissue necrosis factor neutralizingand/or inhibiting activity are also provided in the present invention.In the context of the present invention, TNF neutralizing activity orTNF inhibiting activity refers to the ability of a TNF neutralizingcompound to block at least one biological activity of TNF, such aspreventing TNF from binding to a TNF receptor, blocking production ofTNF by intracellular processing, such as transcription, translation orpost-translational modification, expression on the cell surface,secretion or assembly of the bioactive trimer of TNF. Additionally, TNFneutralizing compounds can act by inducing regulation of metabolicpathways such as those involving the up or down regulation of TNFproduction. Alternatively TNF neutralizing compounds can modulatecellular sensitivity to TNF by decreasing such sensitivity. TNFneutralizing compounds can be selected from the group consisting ofantibodies, or fragments or portions thereof, peptides, peptido mimeticcompounds or organo mimetic compounds that neutralizes TNF activity invitro, in situ or in vivo is considered a TNF neutralizing compound ifused according to the present invention. Screening methods which can beused to determine TNF neutralizing activity of a TNF neutralizingcompound can include in vitro or in vivo assays. Such in vitro assayscan include a TNF cytotoxicity assay, such as a radioimmuno assay whichdetermine a decrease in cell death by contact with TNF, such aschimpanzee or human TNF in isolated or recombinant form, wherein theconcurrent presence of a TNF neutralizing compound reduces the degree orrate of cell death. The cell death can be determined using ID50 valueswhich represent the concentration of a TNF neutralizing compound whichdecreases the cell death rate by 50%. For example, MAb's A2 and cA2 arefound to have ID50 about 17 mg/ml +/−3 mg/ml, such as 14-20 mg/ml, orany range or value therein. Such a TNF cytotoxicity assay is presentedin example II.

Alternatively or additionally, another in vitro assay which can be usedto determine neutralizing activity of a TNF neutralizing compound is anassay which measures the neutralization of TNF induced procoagulantactivity, such as presented in example XI.

Alternatively or additionally, TNF neutralizing activity of a TNFneutralizing compound can be measured by an assay for the neutralizationof TNF induced IL-6 secretion, such as using cultured human umbilicalvein endothelial cells (HUVEC), for example. Also presented in example11.

Alternatively or additionally, in vivo testing of TNF neutralizingactivity of TNF neutralizing compounds can be tested using survival ofmouse given lethal doses of Rh TNF with controlled and variedconcentrations of a TNF neutralizing compound, such as TNF antibodies.Preferably galactosamine sensitive mice are used. For example, using achimeric human anti-TNF antibody as a TNF neutralizing compound, aconcentration of 0.4 milligrams per kilogram TNF antibody resulted in a70-100% increase in survival and a 2.0 mg/kg dose of TNF antibodyresulted in a 90-100% increase in survival rate using such an assay, forexample, as presented in example 12.

Additionally, after TNF neutralizing compounds are tested for safety inanimal models such as chimpanzees, for example as presented in ExampleXVII, TNF neutralizing compounds can be used to treat various TNFrelated pathologies, as described herein, and as presented in ExamplesXVIII-XXII.

Accordingly, any suitable TNF neutralizing compound can be used inmethods according to the present invention. Examples of such TNFneutralizing compound can be selected from the group consisting ofantibodies or portions thereof specific to neutralizing epitopes of TNF,p55 receptors, p75 receptors, or complexes thereof, portions of TNFreceptors which bind TNF, peptides which bind TNF, any peptido mimeticdrugs which bind TNF and any organo mimetic drugs that block TNF.

Such TNF neutralizing compounds can be determined by routineexperimentation based on the teachings and guidance presented herein, bythose skilled in the relevant arts.

Structural Analogs of Anti-TNF Antibodies and Anti-TNF Peptides

Structural analogs of anti-TNF Abs and peptides of the present inventionare provided by known method steps based on the teaching and guidancepresented herein.

Knowledge of the three-dimensional structures of proteins is crucial inunderstanding how they function. The three-dimensional structures ofmore than 400 proteins are currently available in protein structuredatabases (in contrast to around 15,000 known protein sequences insequence databases). Analysis of these structures shows that they fallinto recognizable classes of motifs. It is thus possible to model athree-dimensional structure of a protein based on the proteins homologyto a related protein of known structure. Many examples are known wheretwo proteins that have relatively low sequence homology, can have verysimilar three dimensional structures or motifs.

In recent years it has become possible to determine the threedimensional structures of proteins of up to about 15 kDa by nuclearmagnetic resonance (NMR). The technique only requires a concentratedsolution of pure protein. No crystals or isomorphous derivatives areneeded. The structures of a number proteins have been determined by thismethod. The details of NMR structure determination are well-known in theart (See, e.g., Wuthrich, NMR of Proteins and Nucleic Acids, Wiley, NewYork, 1986; Wuthrich, K. Science 243:45-50 (1989); Clore et al., Crit.Rev. Bioch. Molec. Biol. 24:479-564 (1989); Cooke et al. Bioassays8:52-56 (1988), which references are hereby incorporated herein byreference).

In applying this approach, a variety of ¹H NMR 2D data sets arecollected for anti-TNF Abs and/or anti-TNF peptides of the presentinvention. These are of two main types. One type, COSY (CorrelatedSpectroscopy) identifies proton resonances that are linked by chemicalbonds. These spectra provide information on protons that are linked bythree or less covalent bonds. NOESY (nuclear Overhauser enhancementspectroscopy) identifies protons which are close in space (less than 0.5nm). Following assignment of the complete spin system, the secondarystructure is defined by NOESY. Cross peaks (nuclear Overhauser effectsor NOE's) are found between residues that are adjacent in the primarysequence of the peptide and can be seen for protons less than 0.5 nmapart. The data gathered from sequential NOE's combined with amideproton coupling constants and NOE's from non-adjacent amino acids, thatare adjacent to the secondary structure, are used to characterize thesecondary structure of the polypeptides. Aside from predicting secondarystructure, NOE's indicate the distance that protons are in space in boththe primary amino acid sequence and the secondary structures. Tertiarystructure predictions are determined, after all the data are considered,by a “best fit” extrapolation.

Types of amino acid are first identified using through-bondconnectivities. The second step is to assign specific amino acids usingthrough-space connectivities to neighboring residues, together with theknown amino acid sequence. Structural information is then tabulated andis of three main kinds: The NOE identifies pairs of protons which areclose in space, coupling constants give information on dihedral anglesand slowly exchanging amide protons give information on the position ofhydrogen bonds. The restraints are used to compute the structure using adistance geometry type of calculation followed by refinement usingrestrained molecular dynamics. The output of these computer programs isa family of structures which are compatible with the experimental data(i.e. the set of pairwise <0.5 nm distance restraints). The better thatthe structure is defined by the data, the better the family ofstructures can be superimposed, (i.e., the better the resolution of thestructure). In the better defined structures using NMR, the position ofmuch of backbone (i.e. the amide, Cα and carbonyl atoms) and the sidechains of those amino acids that lie buried in the core of the moleculecan be defined as clearly as in structures obtained by crystallography.The side chains of amino acid residues exposed on the surface arefrequently less well defined, however. This probably reflects the factthat these surface residues are more mobile and can have no fixedposition. (In a crystal structure this might be seen as diffuse electrondensity).

Thus, according to the present invention, use of NMR spectroscopic datais combined with computer modeling to arrive structural analogs of atleast portions of anti-TNF Abs and peptides based on a structuralunderstanding of the topography. Using this information, one of ordinaryskill in the art will know how to achieve structural analogs of anti-TNFAbs and/or peptides, such as by rationally-based amino acidsubstitutions allowing the production of peptides in which the TNFbinding affinity is modulated in accordance with the requirements of theexpected therapeutic or diagnostic use of the molecule, preferably, theachievement of greater specificity for TNF binding.

Alternatively, compounds having the structural and chemical featuressuitable as anti-TNF therapeutics and diagnostics provide structuralanalogs with selective TNF affinity. Molecular modeling studies of TNFbinding compounds, such as TNF receptors, anti-TNF antibodies, or otherTNF binding molecules, using a program such as MACROMODEL®, INSIGHT®,and DISCOVER® provide such spatial requirements and orientation of theanti-TNF Abs and/or peptides according to the present invention. Suchstructural analogs of the present invention thus provide selectivequalitative and quantitative anti-TNF activity in vitro, in situ and/orin vivo.

Therapeutic Methods for Treating TNF-Related Pathologies The anti-TNFpeptides, antibodies, fragments and/or derivatives of the presentinvention are useful for treating a subject having a pathology orcondition associated with abnormal levels of a substance reactive withan anti-TNF antibody, in particular TNF, such as TNFα or TNFβ, in excessof, or less than, levels present in a normal healthy subject, where suchexcess or diminished levels occur in a systemic, localized or particulartissue type or location in the body. Such tissue types can include, butare not limited to, blood, lymph, CNS, liver, kidney, spleen, heartmuscle or blood vessels, brain or spinal cord white matter or greymatter, cartilage, ligaments, tendons, lung, pancreas, ovary, testes,prostrate. Increased or decreased TNF concentrations relative to normallevels can also be localized to specific regions or cells in the body,such as joints, nerve blood vessel junctions, bones, specific tendons orligaments, or sites of infection, such as bacterial or viral infections.

TNF related pathologies include, but are not limited to, the following:

(A) acute and chronic immune and autoimmune pathologies, such assystemic lupus erythematosus (SLE) rheumatoid arthritis, thyroidosis,graft versus host disease, scleroderma, diabetes mellitus, Graves'disease, and the like;

(B) infections, including, but not limited to, sepsis syndrome,cachexia, circulatory collapse and shock resulting from acute or chronicbacterial infection, acute and chronic parasitic and/or infectiousdiseases, bacterial, viral or fungal, such as a HIV, AIDS (includingsymptoms of cachexia, autoimmune disorders, AIDS dementia complex andinfections);

(C) inflammatory diseases, such as chronic inflammatory pathologies andvacsular inflammatory pathologies, including chronic inflammatorypathologies such as sarcoidosis, chronic inflammatory bowel disease,ulcerative colitis, and Crohn's pathology and vascular inflammatorypathologies, such as, but not limited to, disseminated intravascularcoagulation, atherosclerosis, and Kawasaki's pathology:

(D) neurodegenerative diseases, including, but are not limited to,

demyelinating diseases, such as multiple sclerosis and acute transversemyelitis;

extrapyramidal and cerebellar disorders' such as lesions of thecorticospinal system;

disorders of the basal ganglia or cerebellar disorders;

hyperkinetic movement disorders such as Huntington's Chorea and senilechorea;

drug-induced movement disorders, such as those induced by drugs whichblock CNS dopamine receptors;

hypokinetic movement disorders, such as Parkinson's disease;

Progressive supranucleo palsy;

Cerebellar and Spinocerebellar Disorders, such as astructural lesions ofthe cerebellum;

spinocerebellar degenerations (spinal ataxia, Friedreich's ataxia,cerebellar cortical degenerations, multiple systems degenerations(Mencel, Dejerine-Thomas, Shi-Drager, and Machado-Joseph); and systemicdisorders (Refsum's disease, abetalipoprotemia, ataxia, telangiectasia,and mitochondrial multi.system disorder);

demyelinating core disorders, such as multiple sclerosis, acutetransverse myelitis;

disorders of the motor unit, such as neurogenic muscular atrophies(anterior horn cell degeneration, such as amyotrophic lateral sclerosis,infantile spinal muscular atrophy and juvenile spinal muscular atrophy);Alzheimer's disease; Down's Syndrome in middle age; Diffuse Lewy bodydisease; Senile Dementia of Lewy body type; Wernicke-Korsakoff syndrome;chronic alcoholism; Creutzfeldt-Jakob disease; Subacute sclerosingpanencephalitis, Hallerrorden-Spatz disease; and Dementia pugilistica,or any subset thereof;

(E) malignant pathologies involving TNF-secreting tumors or othermalignancies involving TNF, such as, but not limited to leukemias(acute, chronic myelocytic, chronic lymphocytic and/or myelodyspasticsyndrome); lymphomas (Hodgkin's and non-Hodgkin's lymphomas, such asmalignant lymphomas (Burkitt's lymphoma or Mycosis fungoides)); and

(F) alcohol-induced hepatitis.

See, e.g., Berkow et al, eds., The Merck Manual, 16th edition, chapter11, pp 1380-1529, Merck and Co., Rahway, N.J., 1992, which reference,and references cited therein, are entirely incorporated herein byreference.

Such treatment comprises parenterally administering a single or multipledoses of the antibody, fragment or derivative. Preferred for humanpharmaceutical use are high affinity potent hTNFα-inhibiting and/orneutralizing murine and chimeric antibodies, fragments and regions ofthis invention.

Anti-TNF peptides or MAbs of the present invention can be administeredby any means that enables the active agent to reach the agent's site ofaction in the body of a mammal. In the case of the antibodies of thisinvention, the primary focus is the ability to reach and bind with TNFreleased by monocytes and macrophages or other TNF producing cells.Because proteins are subject to being digested when administered orally,parenteral administration, i.e., intravenous, subcutaneous,intramuscular, would ordinarily be used to optimize absorption.

Therapeutic Administration

Anti-TNF peptides and/or MAbs of the present invention can beadministered either as individual therapeutic agents or in combinationwith other therapeutic agents. They can be administered alone, but aregenerally administered with a pharmaceutical carrier selected on thebasis of the chosen route of administration and standard pharmaceuticalpractice.

The dosage administered will, of course, vary depending upon knownfactors such as the pharmacodynamic characteristics of the particularagent, and its mode and route of administration; age, health, and weightof the recipient; nature and extent of symptoms, kind of concurrenttreatment, frequency of treatment, and the effect desired. Usually adaily dosage of active ingredient can be about 0.01 to 100 milligramsper kilogram of body weight. Ordinarily 1.0 to 5, and preferably 1 to 10milligrams per kilogram per day given in divided doses 1 to 6 times aday or in sustained release form is effective to obtain desired results.

As a non-limiting example, treatment of TNF-related pathologies humansor animals can be provided as a daily dosage of anti-TNF peptides,monoclonal chimeric and/or murine antibodies of the present invention0.1 to 100 mg/kg, such as 0.5, 0.9, 1.0, 1.1, 1.5, 2, 3, 4, 5, 6, 7, 8,9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26,27, 28, 29, 30, 40, 45, 50, 60, 70, 80, 90 or 100 mg/kg, per day, on atleast one of day 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16,17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34,35, 36, 37, 38, 39, or 40, or alternatively, at least one of week 1, 2,3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19 or 20, orany combination thereof, using single or divided doses of every 24, 12,8, 6, 4, or 2 hours, or any combination thereof.

Since circulating concentrations of TNF tend to be extremely low, in therange of about 10 pg/ml in non-septic individuals, and reaching about 50pg/ml in septic patients and above 100 pg/ml in the sepsis syndrome(Hammerle, A. F. et al., 1989, infra) or can be only be detectable atsites of TNF-mediated pathology, it is preferred to use high affinityand/or potent in vivo TNF-inhibiting and/or neutralizing antibodies,fragments or regions thereof, for both TNF immunoassays and therapy ofTNF-mediated pathology. Such antibodies, fragments, or regions, willpreferably have an affinity for hTNFα, expressed as Ka, of at least 10⁸M⁻¹, more preferably, at least 10⁹ M⁻¹, such as 10⁸-10¹⁰ M⁻¹, 5×10⁸ M⁻¹,8×10⁸ M⁻¹, 2×10⁹ M⁻¹, 4×10⁹ M⁻¹, 6×10⁹ M⁻¹, 8×10⁹ M⁻¹, or any range orvalue therein.

Preferred for human therapeutic use are high affinity murine andchimeric antibodies, and fragments, regions and derivatives havingpotent in vivo TNFα-inhibiting and/or neutralizing activity, accordingto the present invention, that block TNF-induced IL-6 secretion. Alsopreferred for human therapeutic uses are such high affinity murine andchimeric anti-TNFα antibodies, and fragments, regions and derivativesthereof, that block TNF-induced procoagulant activity, includingblocking of TNF-induced expression of cell adhesion molecules such asELAM-1 and ICAM-1 and blocking of TNF mitogenic activity, in vivo, insitu, and in vitro.

Dosage forms (composition) suitable for internal administrationgenerally contain from about 0.1 milligram to about 500 milligrams ofactive ingredient per unit. In these pharmaceutical compositions theactive ingredient will ordinarily be present in an amount of about0.5-95% by weight based on the total weight of the composition.

For parenteral administration, anti-TNF peptides or antibodies can beformulated as a solution, suspension, emulsion or lyophilized powder inassociation with a pharmaceutically acceptable parenteral vehicle.Examples of such vehicles are water, saline, Ringer's solution, dextrosesolution, and 5% human serum albumin. Liposomes and nonaqueous vehiclessuch as fixed oils can also be used. The vehicle or lyophilized powdercan contain additives that maintain isotonicity (e.g., sodium chloride,mannitol) and chemical stability (e.g., buffers and preservatives). Theformulation is sterilized by commonly used techniques.

Suitable pharmaceutical carriers are described in the most recentedition of Remington's Pharmaceutical Sciences, A. Osol, a standardreference text in this field of art.

For example, a parenteral composition suitable for administration byinjection is prepared by dissolving 1.5% by weight of active ingredientin 0.9% sodium chloride solution.

Anti-TNF peptides and/or antibodies of this invention can be adapted fortherapeutic efficacy by virtue of their ability to mediateantibody-dependent cellular cytotoxicity (ADCC) and/orcomplement-dependent cytotoxicity (CDC) against cells having TNFassociated with their surface. For these activities, either anendogenous source or an exogenous source of effector cells (for ADCC) orcomplement components (for CDC) can be utilized. The murine and chimericantibodies, fragments and regions of this invention, their fragments,and derivatives can be used therapeutically as immunoconjugates (see forreview: Dillman, R. O., Ann. Int. Med. 111:592-603 (1989)). Suchpeptides or Abs can be coupled to cytotoxic proteins, including, but notlimited to ricin-A, Pseudomonas toxin and Diphtheria toxin. Toxinsconjugated to antibodies or other ligands or peptides are well known inthe art (see, for example, Olsnes, S. et al., Immunol. Today 10:291-295(1989)). Plant and bacterial toxins typically kill cells by disruptingthe protein synthetic machinery.

Anti-TNF peptides and/or antibodies of this invention can be conjugatedto additional types of therapeutic moieties including, but not limitedto, radionuclides, therapeutic agents, cytotoxic agents and drugs.Examples of radionuclides which can be coupled to antibodies anddelivered in vivo to sites of antigen include ²¹²Bi, ¹³¹I, ¹⁸⁶Re, and⁹⁰Y, which list is not intended to be exhaustive. The radionuclidesexert their cytotoxic effect by locally irradiating the cells, leadingto various intracellular lesions, as is known in the art ofradiotherapy.

Cytotoxic drugs which can be conjugated to anti-TNF peptides and/orantibodies and subsequently used for in vivo therapy include, but arenot limited to, daunorubicin, doxorubicin, methotrexate, and MitomycinC. Cytotoxic drugs interfere with critical cellular processes includingDNA, RNA, and protein synthesis. For a description of these classes ofdrugs which are well known in the art, and their mechanisms of action,see Goodman, et al., Goodman and Gilman's THE PHARMACOLOGICAL BASIS OFTHERAPEUTICS, 8th Ed., Macmillan Publishing Co., 1990.

Anti-TNF peptides and/or antibodies of this invention can beadvantageously utilized in combination with other monoclonal or murineand chimeric antibodies, fragments and regions, or with lymphokines orhemopoietic growth factors, etc., which serve to increase the number oractivity of effector cells which interact with the antibodies.

Anti-TNF peptides and/or antibodies, fragments or derivatives of thisinvention can also be used in combination with TNF therapy to blockundesired side effects of TNF. Recent approaches to cancer therapy haveincluded direct administration of TNF to cancer patients orimmunotherapy of cancer patients with lymphokine activated killer (LAK)cells (Rosenberg et al., New Eng. J. Med. 313:1485-1492 (1985)) or tumorinfiltrating lymphocytes (TIL) (Kurnick et al. (Clin. Immunol.Immunopath. 38:367-380 (1986); Kradin et al., Cancer Immunol.Immunother. 24:76-85 (1987); Kradin et al., Transplant. Proc. 20:336-338(1988)). Trials are currently underway using modified LAK cells or TILwhich have been transfected with the TNF gene to produce large amountsof TNF. Such therapeutic approaches are likely to be associated with anumber of undesired side effects caused by the pleiotropic actions ofTNF as described herein and known in the related arts. According to thepresent invention, these side effects can be reduced by concurrenttreatment of a subject receiving TNF or cells producing large amounts ofTIL with the antibodies, fragments or derivatives of the presentinvention. Effective doses are as described above. The dose level willrequire adjustment according to the dose of TNF or TNF-producing cellsadministered, in order to block side effects without blocking the mainanti-tumor effect of TNF. One of ordinary skill in the art will know howto determine such doses without undue experimentation.

Treatment of Arthritis. In rheumatoid arthritis, the main presentingsymptoms are pain, stiffness, swelling, and loss of function (Bennett JC. The etiology of rheumatoid arthritis. In Textbook of Rheumatology(Kelley W N, Harris E D, Ruddy S, Sledge C B, eds.) W B Saunders,Philadelphia pp 879-886, 1985). The multitude of drugs used incontrolling such symptoms seems largely to reflect the fact that none isideal. Although there have been many years of intense research into thebiochemical, genetic, microbiological, and immunological aspects ofrheumatoid arthritis, its pathogenesis is not completely understood, andnone of the treatments clearly stop progression of joint destruction(Harris E D. Rheumatoid Arthritis: The clinical spectrum. In Textbook ofRheumatology (Kelley, et al., eds.) W B Saunders, Philadelphia pp915-990, 1985).

TNFα is of major importance in the pathogenesis of rheumatoid arthritis.TNFα is present in rheumatoid arthritis joint tissues and synovial fluidat the protein and mRNA level (Buchan G, Barrett K, Turner M, Chantry D,Maini R N, and Feldmann M. Interleukin-1 and tumour necrosis factor mRNAexpression in rheumatoid arthritis: prolonged production of IL-1_(α) .Clin. Exp. Immunol 73: 449-455, 1988), indicating local synthesis.However detecting TNFα in rheumatoid arthritis joints even in quantitiessufficient for bioactivation does not necessarily indicate that it isimportant in the pathogenesis of rheumatoid arthritis, nor that it is agood candidate therapeutic target. In order to address these questions,the effects of anti-TNF antibody and peptides (rabbit or monoclonal) onrheumatoid joint cell cultures, and for comparison, osteoarthritic cellcultures, have been studied. IL-1 production was abolished, showing TNFαas a suitable therapeutic target for the therapy of rheumatoidarthritis, since anti-TNFα blocks both TNF and IL-1, the two cytokinesknown to be involved in cartilage and bone destruction (Brennan et al.,Lancet 11: 244-247, 1989).

Subsequent studies in rheumatoid arthritis tissues have supported thishypothesis. Anti-TNF Abs abrogated the production of anotherproinflammatory cytokine, GM-CSF (Haworth et al., Eur. J. Immunol.21:2575-2579, 1991). This observation has been independently confirmed(Alvaro-Gracia et al., 1991). It has also been demonstrated thatanti-TNF diminishes cell adhesion and HLA class II expression inrheumatoid arthritis joint cell cultures.

Diagnostic Methods

The present invention also provides the above anti-TNF peptides andantibodies, detectably labeled, as described below, for use indiagnostic methods for detecting TNFα in patients known to be orsuspected of having a TNFα-mediated condition.

Anti-TNF peptides and/or antibodies of the present invention are usefulfor immunoassays which detect or quantitate TNF, or anti-TNF antibodies,in a sample. An immunoassay for TNF typically comprises incubating abiological sample in the presence of a detectably labeled high affinityanti-TNF peptide and/or antibody of the present invention capable ofselectively binding to TNF, and detecting the labeled peptide orantibody which is bound in a sample. Various clinical assay proceduresare well known in the art, e.g., as described in Immunoassays for the80's, A. Voller et al., eds., University Park, 1981.

Thus, an anti-TNF peptide or antibody, can be added to nitrocellulose,or other solid support which is capable of immobilizing cells, cellparticles or soluble proteins. The support can then be washed withsuitable buffers followed by treatment with the detectably labeledTNF-specific peptide or antibody. The solid phase support can then bewashed with the buffer a second time to remove unbound peptide orantibody. The amount of bound label on the solid support can then bedetected by known method steps.

By “solid phase support” or “carrier” is intended any support capable ofbinding peptide, antigen or antibody. Well-known supports or carriers,include glass, polystyrene, polypropylene, polyethylene, dextran, nylon,amylases, natural and modified celluloses, polyacrylamides, agaroses,and magnetite. The nature of the carrier can be either soluble to someextent or insoluble for the purposes of the present invention. Thesupport material can have virtually any possible structuralconfiguration so long as the coupled molecule is capable of binding toTNF or an anti-TNF antibody. Thus, the support configuration can bespherical, as in a bead, or cylindrical, as in the inside surface of atest tube, or the external surface of a rod. Alternatively, the surfacecan be flat such as a sheet, culture dish, test strip, etc. Preferredsupports include polystyrene beads. Those skilled in the art will knowmany other suitable carriers for binding antibody, peptide or antigen,or can ascertain the same by routine experimentation.

Well known method steps can determine binding activity of a given lot ofanti-TNF peptide and/or antibody. Those skilled in the art can determineoperative and optimal assay conditions by routine experimentation.

Detectably labeling a TNF-specific peptide and/or antibody can beaccomplished by linking to an enzyme for use in an enzyme immunoassay(EIA), or enzyme-linked immunosorbent assay (ELISA). The linked enzymereacts with the exposed substrate to generate a chemical moiety whichcan be detected, for example, by spectrophotometric, fluorometric or byvisual means. Enzymes which can be used to detectably label theTNF-specific antibodies of the present invention include, but are notlimited to, malate dehydrogenase, staphylococcal nuclease,delta-5-steroid isomerase, yeast alcohol dehydrogenase,alpha-glycerophosphate dehydrogenase, triose phosphate isomerase,horseradish peroxidase, alkaline phosphatase, asparaginase, glucoseoxidase, beta-galactosidase, ribonuclease, urease, catalase,glucose-6-phosphate dehydrogenase, glucoamylase andacetylcholinesterase.

By radioactively labeling the TNF-specific anti-bodies, it is possibleto detect TNF through the use of a radioimmunoassay (RIA) (see, forexample, Work, et al., Laboratory Techniques and Biochemistry inMolecular Biology, North Holland Publishing Company, N.Y. (1978). Theradio-active isotope can be detected by such means as the use of a gammacounter or a scintillation counter or by autoradiography. Isotopes whichare particularly useful for the purpose of the present invention are:³H, ¹²⁵I, ¹³¹I, ³⁵S, ¹⁴C, and, preferably, ¹²⁵I.

It is also possible to label the TNF-specific antibodies with afluorescent compound. When the fluorescent labeled antibody is exposedto light of the proper wave length, its presence can then be detecteddue to fluorescence. Among the most commonly used fluorescent labellingcompounds are fluorescein isothiocyanate, rhodamine, phycoerythrin,phycocyanin, allophycocyanin, o-phthaldehyde and fluorescamine.

The TNF-specific antibodies can also be detectably labeled usingfluorescence-emitting metals such as ¹⁵²Eu, or others of the lanthanideseries. These metals can be attached to the TNF-specific antibody usingsuch metal chelating groups as diethylenetriaminepentaacetic acid (DTPA)or ethylenediamine-tetraacetic acid (EDTA).

The TNF-specific antibodies also can be detectably labeled by couplingto a chemiluminescent compound. The presence of the chemiluminescentlylabeled antibody is then determined by detecting the presence ofluminescence that arises during the course of a chemical reaction.Examples of particularly useful chemiluminescent labeling compounds areluminol, isoluminol, theromatic acridinium ester, imidazole, acridiniumsalt and oxalate ester.

Likewise, a bioluminescent compound can be used to label theTNF-specific antibody, fragment or derivative of the present invention.Bioluminescence is a type of chemiluminescence found in biologicalsystems in which a catalytic protein increases the efficiency of thechemiluminescent reaction. The presence of a bioluminescent protein isdetermined by detecting the presence of luminescence. Importantbioluminescent compounds for purposes of labeling are luciferin,luciferase and aequorin.

Detection of the TNF-specific antibody, fragment or derivative can beaccomplished by a scintillation counter, for example, if the detectablelabel is a radioactive gamma emitter, or by a fluorometer, for example,if the label is a fluorescent material. In the case of an enzyme label,the detection can be accomplished by colorometric methods which employ asubstrate for the enzyme. Detection can also be accomplished by visualcomparison of the extent of enzymatic reaction of a substrate incomparison with similarly prepared standards.

For the purposes of the present invention, the TNF which is detected bythe above assays can be present in a biological sample. Any samplecontaining TNF can be used. Preferably, the sample is a biological fluidsuch as, for example, blood, serum, lymph, urine, inflammatory exudate,cerebrospinal fluid, amniotic fluid, a tissue extract or homogenate, andthe like. However, the invention is not limited to assays using onlythese samples, it being possible for one of ordinary skill in the art todetermine suitable conditions which allow the use of other samples.

In situ detection can be accomplished by removing a histologicalspecimen from a patient, and providing the combination of labeledantibodies of the present invention to such a specimen. The antibody (orfragment) is preferably provided by applying or by overlaying thelabeled antibody (or fragment) to a biological sample. Through the useof such a procedure, it is possible to determine not only the presenceof TNF but also the distribution of TNF in the examined tissue. Usingthe present invention, those of ordinary skill will readily perceivethat any of a wide variety of histological methods (such as stainingprocedures) can be modified in order to achieve such in situ detection.

The antibody, fragment or derivative of the present invention can beadapted for utilization in an immunometric assay, also known as a“two-site” or “sandwich” assay. In a typical immunometric assay, aquantity of unlabeled antibody (or fragment of antibody) is bound to asolid support that is insoluble in the fluid being tested and a quantityof detectably labeled soluble antibody is added to permit detectionand/or quantitation of the ternary complex formed between solid-phaseantibody, antigen, and labeled antibody.

Typical, and preferred, immunometric assays include “forward” assays inwhich the antibody bound to the solid phase is first contacted with thesample being tested to extract the TNF from the sample by formation of abinary solid phase antibody-TNF complex. After a suitable incubationperiod, the solid support is washed to remove the residue of the fluidsample, including unreacted TNF, if any, and then contacted with thesolution containing a known quantity of labeled antibody (whichfunctions as a “reporter molecule”). After a second incubation period topermit the labeled antibody to complex with the TNF bound to the solidsupport through the unlabeled antibody, the solid support is washed asecond time to remove the unreacted labeled antibody. This type offorward sandwich assay can be a simple “yes/no” assay to determinewhether TNF is present or can be made quantitative by comparing themeasure of labeled antibody with that obtained for a standard samplecontaining known quantities of TNF. Such “two-site” or “sandwich” assaysare described by Wide (Radioimmune Assay Method, Kirkham, ed.,Livingstone, Edinburgh, 1970, pp. 199-206).

Other type of “sandwich” assays, which can also be useful with TNF, arethe so-called “simultaneous” and “reverse” assays. A simultaneous assayinvolves a single incubation step wherein the antibody bound to thesolid support and labeled antibody are both added to the sample beingtested at the same time. After the incubation is completed, the solidsupport is washed to remove the residue of fluid sample and uncomplexedlabeled antibody. The presence of labeled antibody associated with thesolid support is then determined as it would be in a conventional“forward” sandwich assay.

In the “reverse” assay, stepwise addition first of a solution of labeledantibody to the fluid sample followed by the addition of unlabeledantibody bound to a solid support after a suitable incubation period, isutilized. After a second incubation, the solid phase is washed inconventional fashion to free it of the residue of the sample beingtested and the solution of unreacted labeled antibody. The determinationof labeled antibody associated with a solid support is then determinedas in the “simultaneous” and “forward” assays. In one embodiment, acombination of antibodies of the present invention specific for separateepitopes can be used to construct a sensitive three-siteimmunoradiometric assay.

TNF REMOVAL FROM SOLUTIONS

The murine and chimeric antibodies, fragments and regions, fragments, orderivatives of this invention, attached to a solid support, can be usedto remove TNF from fluids or tissue or cell extracts. In a preferredembodiment, they are used to remove TNF from blood or blood plasmaproducts. In another preferred embodiment, the murine and chimericantibodies, fragments and regions are advantageously used inextracorporeal immunoadsorbent devices, which are known in the art (see,for example, Seminars in Hematology, 26 (2 Suppl. 1) (1989)). Patientblood or other body fluid is exposed to the attached antibody, resultingin partial or complete removal of circulating TNF (free or in immunecomplexes), following which the fluid is returned to the body. Thisimmunoadsorption can be implemented in a continuous flow arrangement,with or without interposing a cell centrifugation step. See, forexample, Terman, et al., J. Immunol. 117:1971-1975 (1976).

Having now generally described the invention, the same will be furtherunderstood by reference to certain specific examples which are includedherein for purposes of illustration only and are not intended to belimiting unless otherwise specified.

EXAMPLE I Production a Mouse Anti-Human TNF mAb

To facilitate clinical study of TNF mAb a high-affinity potentinhibiting and/or neutralizing mouse anti-human TNF IgG1 mAb designatedA2 was produced.

Female BALB/c mice, 10 weeks old, were obtained from the JacksonLaboratory (Bar Harbor, Me.). Forty μg of purified E. coli-derivedrecombinant human TNF (rhTNF) emulsified with an equal volume ofcomplete Freund's adjuvant (obtained from Difco Laboratories) in 0.4 mlwas injected subcutaneously and intraperitoneally (i.p.) into a mouse.One week later, an injection of 5 μg of rhTNF in incomplete Freund'sadjuvant was given i.p. followed by four consecutive i.p. injections of10 μg of TNF without adjuvant. Eight weeks after the last injection, themouse was boosted i.p. with 10 μg of TNF.

Four days later, the mouse was sacrificed, the spleen was obtained and aspleen cell suspension was prepared. Spleen cells were fused with cellsof the nonsecreting hybridoma, Sp2/0 (ATCC CRL1581), at a 4:1 ratio ofspleen cells to Sp2/0 cells, in the presence of 0.3 ml of 30%polyethylene glycol, PEG 1450. After incubation at 37° C. for 6 hours,the fused cells were distributed in 0.2 ml aliquots into 96-well platesat concentrations of 2×10⁴ SP2/0 cells per well. Feeder cells, in theform of 5×10⁴ normal BALB/c spleen cells, were added to each well.

The growth medium used consisted of RPMl-1640 medium, 10%heat-inactivated fetal bovine serum (FBS) (HYCLONE), 0.1 mM minimumessential medium (MEM) nonessential amino acids, 1 mM sodium pyruvate, 2mM L-glutamine, 100 U/ml penicillin, 100 μg/ml streptomycin (GIBCOLaboratories) and, for selection, hypoxanthine-aminopterin-thymidine(HAT) (Boehringer Mannheim). A solid-phase radioimmunoassay (RIA) wasemployed for screening supernatants for the presence of mAbs specificfor rhTNFα. This assay is described in Example II, below. The backgroundbinding in this assay was about 500 cpm. A supernatant was consideredpositive if it yielded binding of 2000 cpm or higher.

Of 322 supernatants screened, 25 were positive by RIA. Of these 25, theone with the highest binding (4800 cpm) was designated A2. Positivewells were subcloned at limiting dilution on mouse feeder cells. Uponfurther analysis of the supernatants in neutralization assays, A2 wasfound to be the only positive clone showing potent inhibiting and/orneutralizing activity. Thus, the hybridoma line A2 was selected. Thisline was maintained in RPMl-1640 medium with 10% FBS (GIBCO), 0.1 mMnonessential amino acids, 1 mM sodium pyruvate, 2 mM L-glutamine, 100U/ml penicillin and 100 μg/ml streptomycin.

Alternatively, anti-TNF antibodies which inhibit TNF biological activitycan be screened by binding to peptide including at least 5 amino acidsof residues 87-108 or both residues 59-80 and 87-108 of TNF (of SEQ IDNO:1) or combinations of peptides contained therein, which are used inplace of the rTNF protein, as described above.

EXAMPLE II Characterization of an Anti-TNF Antibody of the PresentInvention

Radioimmunoassays

E. coli-derived rhTNF was diluted to 1 μg/ml in BCB buffer, pH 9.6, and0.1 ml of the solution was added to each assay well. After incubation at4° C. overnight, the wells were washed briefly with BCB, then sealedwith 1% bovine incubated with 40 pg/ml of natural (GENZYME, Boston,Mass.) or recombinant (SUNTORY, Osaka, Japan) human TNFα with varyingconcentrations of mAb A2 in the presence of 20 μg/ml cycloheximide at39° C. overnight. Controls included medium alone or medium +TNF in eachwell. Cell death was measured by staining with naphthol blue-black, andthe results read spectrophotometrically at 630 nm. Absorbance at thiswave length correlates with the number of live cells present.

It was found that A2 inhibited or neutralized the cytotoxic effect ofboth natural and rhTNF in a dose-dependent manner (FIG. 3).

In another experiment, the specificity of this inhibiting and/orneutralizing activity was tested. A673/6 cells were seeded at 3×10⁴cells/well 20 hr before the TNF bioassay. Two-fold serial dilutions ofrhTNF, E. coli-derived recombinant human lymphotoxin (TNFβ), and E.coli-derived recombinant murine TNF were prepared. The A2 hybridomasupernatant was added to an equal volume of the diluted TNFpreparations, and the mixtures were incubated at room temperature for 30min. Aliquots of 0.1 ml were transferred to the wells containing A673/6cells, 20 μg/ml of cycloheximide was added, and the cells were incubatedat 39° C. overnight. The cells were then fixed and stained forevaluation of cytotoxicity. The results indicate that mAb A2specifically inhibited or neutralized the cytotoxicity of rhTNFα,whereas it had no effect on human lymphotoxin (TNFβ) (FIG. 4) or murineTNF (FIG. 5).

Experiments were next performed to analyze the cross-reactivity of mAbA2 with TNF derived from non-human primates. Monocytes isolated fromB514 (baboon), J91 (cynomolgus) and RH383 (rhesus) blood by Ficollgradient centrifugation and adherence, were incubated at 1×10⁵cells/well in RPMl 1640 medium with 5% FBS and 2 μg/ml of E. coli LPSfor 3 or 16 hr at 37° C. to induce TNF production. Supernatants fromduplicate wells were pooled and stored at 4° C. for less than 20 hruntil the TNF bioassay was performed, as described above, using A673/6cells. Two-fold dilutions of the culture supernatants were mixed witheither medium or purified mAb A2 at a final concentration of 1 μg/ml,incubated at room temperature for 30 min and aliquots transferred to theindicator cells. The results showed that mAb A2 failed to significantlyinhibit or neutralize the cytotoxic activity of TNF produced by baboon,cynomolgus and rhesus monkey monocytes.

A further experiment was conducted with chimpanzee TNF. Monocytesisolated from CH563 (chimpanzee) blood were incubated as described aboveto generate TNF-containing supernatants. The ability of 10 μg/ml of mAbA2 to inhibit or neutralize the bioactivity of these supernatants wasassayed as above. Human TNF was used as a positive control. Results,shown in FIG. 6, indicate that mAb A2 had potent inhibiting and/orneutralizing activity for chimpanzee TNF, similar to that for human TNF(FIG. 7).

The inhibiting and/or neutralizing activity of mAb A2 was compared withthree other murine mAbs specific for human TNF, termed TNF-1, TNF-2 andTNF-3, and a control mAb. Two-fold serial dilutions of purified mAbswere mixed with rhTNF (40 pg/ml), incubated at room temperature for 30min, and aliquots tested for TNF bioactivity as above. It was found thatmAbs TNF-1, TNF-2 and TNF-3 each had a similar moderate degree ofinhibiting and/or neutralizing activity. In contrast, mAb A2 had muchmore potent inhibiting and/or neutralizing activity.

EXAMPLE III General Strategy for Cloning Antibody V and C Genes

The strategy for cloning the V regions for the H and L chain genes fromthe hybridoma A2, which secretes the anti-TNF antibody described above,was based upon the linkage in the genome between the V region and thecorresponding J (joining) region for functionally rearranged (andexpressed) Ig genes. J region DNA probes can be used to screen genomiclibraries to isolate DNA linked to the J regions. Although DNA in thegermline configuration (i.e., unrearranged) would also hybridize to Jprobes, this DNA would not be linked to a Ig V region sequence and canbe identified by restriction enzyme analysis of the isolated clones.

The cloning utilized herein was to isolate V regions from rearranged Hand L chain genes using J_(H) and J_(k) probes. These clones were testedto see if their sequences were expressed in the A2 hybridoma by Northernanalysis. Those clones that contained expressed sequence were clonedinto expression vectors containing human C regions and transfected intomouse myeloma cells to determine if an antibody was produced. Theantibody from producing cells was then tested for binding specificityand functionally compared to the A2 murine antibody.

EXAMPLE IV Construction of a L Chain Genomic Library

To isolate the L chain V region gene from the A2 hybridoma, asize-selected genomic library was constructed using the phage lambdavector charon 27. High molecular weight DNA was isolated from A2hybridoma cells and digested to completion with restriction endonucleaseHindIII. The DNA was then fractionated on a 0.8% agarose gel and the DNAfragments of three different size ranges of approximately 3 kb, 4 kb and6 kb were isolated from the gel by electroelution. The size ranges forlibrary construction were chosen based upon the size of Hind IIIfragments that hybridized on a southern blot with the J_(k) probe. Afterphenol/chloroform extraction and ethanol precipitation, the DNAfragments from each size class were ligated with lambda charon 27 armsand packaged into phage particles in vitro using Gigapack Gold fromStratagene (LaJolla, Calif.).

These libraries were screened directly at a density of approximately20,000 plaques per 150 mm petri dish using a ³²P-labeled J_(k) probe.The mouse L chain J_(k) probe was a 2.7 kb HindIII fragment containingall five J_(k) segments. The probe was labeled with ³²P by randompriming using a kit obtained from Boehringer Mannheim. Free nucleotideswere removed by centrifugation through a Sephadex G-50 column. Thespecific activities of the probe was approximately 10⁹ cpm/μg.

Plaque hybridizations were carried out in 5×SSC, 50% formamide,2×Denhardt's reagent, and 200 μg/ml denatured salmon sperm DNA at 42° C.for 18-20 hours. Final washes were in 0.5×SSC, 0.1% SDS at 65° C.Positive clones were identified after autoradiography.

EXAMPLE V Construction of H Chain Genomic Library

To isolate the V region gene for the A2 H chain, a genomic library wasconstructed in the lambda gt10 vector system. High molecular weight DNAwas digested to completion with restriction endonuclease EcoRI andfragments of approximately 7.5 kb were isolated after agarose gelelectrophoresis. These fragments were ligated with lambda gt10 arms andpackaged into phage particles in vitro using Gigapack Gold.

This library was screened at a density of 20,000 plaques per 150 mmplate using a J_(H) probe. The J_(H) probe was a 2 kb BamHI/EcoRIfragment containing both J3 and J4 segments. The probe was labeled as inExample III and had a similar specific radioactivity. Hybridization andwash conditions were identical to those used in Example III.

EXAMPLE VI Cloning of the TNF-Specific V Gene Regions

Several positive clones were isolated from the H and L chain librariesafter screening approximately 10⁶ plaques from each library using theJ_(H) and J_(k) probes, respectively. Following plaque purification,bacteriophage DNA was isolated for each positive clone, digested witheither EcoRI (H chain clones) or HindIII (L chain clones) andfractionated on 1% agarose gels. The DNA was transferred tonitrocellulose and the blots were hybridized with the J_(H) or the J_(K)probe.

Several H chain clones were obtained that contained 7.5 kb EcoRI DNAencoding fragments of MAbs to the J_(H) probe. For the light chainlibraries, several clones from each of the three size-selected librarieswere isolated that contained HindIII fragments that hybridize to theJ_(k) probe. For the L chain, several independently derived HindIIIfragments of 2.9 kb from the 2 kb library hybridized with a 1250 bp mRNAfrom A2, but not with SP2/0 mRNA (see Example VII). In addition, severalHindIII fragments derived from the 4 kb library hybridized both to theA2 mRNA and the fusion partner mRNA. A 5.7 kb HindIII fragment from the6 kb library did not hybridize to either RNA.

The observed lengths of hybridizing A2 mRNA were the correct sizes for Hand L chain mRNA, respectively. Because the RNA expression wasrestricted to the A2 hybridoma, it was assumed that the 7.5 kb H chainfragments and the 2.9 kb L chain fragments contained the correct Vregion sequences from A2. One example of each type was chosen forfurther study. The important functional test is the demonstration thatthese V regions sequences, when combined with appropriate C regionsequences, are capable of directing the synthesis of an antibody with aspecificity and affinity similar to that of the murine A2 antibody.

The 7.5 kb H chain fragment and the 2.9 kb L chain fragment weresubcloned into plasmid vectors that allow expression of the chimericmouse/human proteins in murine myeloma cells (see Examples VIII and IX).These plasmids were co-transfected into SP2/0 cells to ascertain ifintact antibody molecules were secreted, and if so, if they were of thecorrect specificity and affinity. Control transfections were alsoperformed pairing the putative anti-TNF H chain with an irrelevant, butexpressed, L chain; the putative anti-TNF L chain was also paired withan irrelevant, but expressed, H chain. The results indicated that the7.5 kb H chain fragment could be expressed, whereas the 2.9 kb L chainfragment could not. This was confirmed by DNA sequence analysis thatsuggested portions of the coding region were not in the proper aminoacid reading frame when compared to other known L chain amino acidsequences.

Because the 2.9 kb HindIII fragment appeared not to contain a functionalV gene, the 4.0 kb and 5.7 kb HindIII fragments isolated from L chainlibraries were cloned into expression vectors and tested for expressionof chimeric antibody after co-transfection with the 7.5 kb H chain. The5.7 kb HindIII fragment was incapable of supporting antibody expression,whereas the 4.0 kb HindIII fragment did support antibody expression. Theantibody resulting from the co-transfection of the 7.5 kb putative Hchain V region and the 4.0 kb L chain V region was purified, tested insolid phase TNF binding assay, and found to be inactive. It wasconcluded that the V region contained on the 4.0 kb HindIII fragment wasnot the correct anti-TNF V regions, but was contributed to the hybridomaby the fusion partner. This was subsequently confirmed by sequenceanalysis of cDNA derived from the A2 hybridoma and from the fusionpartner.

Other independently derived L chain clones containing 2.9 kb HindIIIfragments that hybridized with A2 mRNA were characterized in moredetail. Although the restriction maps were similar, the clones fell intotwo classes with respect to the presence or absence of an AccI enzymesite. The original (non-functional) 2.9 kb fragment (designated clone8.3) was missing an AccI site present in some other clones (representedby clone 4.3). The DNA sequence of clone 4.3 was extremely similar toclone 8.3, but contained a single amino acid reading frame with closehomology to known L chains, unlike clone 8.3. The 2.9 kb HindIIIfragment from clone 4.3 was subcloned into the L chain expression vectorand co-transfected with the putative anti-TNF H chain into SP2/0 cells.An antibody was synthesized, purified and tested in the solid phase TNFbinding assay. This antibody bound to TNF, and therefore, the clone 4.3L chain V region was assumed to be the correct one.

The A2 murine hybridoma has been shown to contain at least fourrearranged L chain V region genes. At least two of these are expressedas proteins: clone 4.3 (the correct anti-TNF L chain gene) and the genecontained in the 4.0 kb HindIII fragment (contributed by the fusionpartner). The expression of two L chains implies that the resultingantibody secreted from the murine hybridoma is actually a mixture ofantibodies, some using the correct L chain, some using the incorrect Lchain, and some using one of each. The presence of two different Lchains in the murine A2 antibody has been confirmed by SDS gel andN-terminal protein sequence analysis of the purified antibody. Becauseconstruction of the chimeric A2 antibody involves cloning the individualH and L chain genes and expressing them in a non-producing cell line,the resulting antibody will have only the correct L chain and thereforeshould be a more potent antibody (see Examples X, XI and XII).

EXAMPLE VII Northern Analysis of Cloned DNA

Cloned DNA corresponding to the authentic H and L chain V regions fromthe A2 hybridoma would be expected to hybridize to A2 mRNA.Non-functional DNA rearrangements at either the H or L chain geneticloci should not be expressed.

Ten μg total cellular RNA was subjected to electrophoresis on 1%agarose/formaldehyde gels (Sambrook et al, infra) and transferred tonitrocellulose. Blots were hybridized with random primed DNA probes in50% formamide, 2×Denhardt's solution, 5×SSC, and 200 μg/ml denaturedsalmon sperm DNA at 42° C. for 10 hours. Final wash conditions were0.5×SSC, 0.1% SDS at 65° C.

The subdoned DNA fragment s were labeled with ³²P by random priming andhybridized to Northern blots containing total RNA derived from A2 cellsor from cells of SP2/0, the fusion partner parent of A2. The 7.5 kbEcoRI H chain fragment hybridized with a 2 kb mRNA from A2, but not withSP2/0 mRNA. Similarly, the 2.9 kb L chain HindIII fragment (clone 4.3)hybridized with a 1250 bp mRNA from A2, but not with SP2/0 mRNA. Theobserved lengths of A2 mRNA hybridizing were the correct sizes for H andL chain mRNA, respectively, confirming that the V region sequences onthese DNA fragments are expressed in A2 hybridoma cells.

EXAMPLE VIII Construction of Expression Vectors

The putative L (clone 4.3) and H chain V genes described above werejoined to human kappa and gaimal constant region genes in expressionvectcrs. The 7.5 kb EcoRI fragment corresponding to the putative V_(H)region gene from A2 was cloned into an expression vector containing thehuman C_(gamma1) gene and the Ecogpt gene to yield the plasmiddesignated pA2HG1apgpt (see FIG. 8).

The 2.9 kb putative V_(L) fragment from clone 4.3 was cloned into avector containing the human kappa C_(k) gene and the Ecogpt gene toallow selection in mammalian cells. The resulting plasmid was designatedpA2HuKapgpt (See FIG. 8).

EXAMPLE IX Expression of Chimeric Antibody Genes

To express the chimeric H and L chain genes, the expression plasmidswere transfected into cells of the non-producing mouse myeloma cellline, SP2/0. Plasmid DNA to be transfected was purified by centrifugingto equilibrium in ethidium bromide/cesium chloride gradients twice.Plasmid DNA (10-50 μg) was added to 10⁷ SP2/0 cells in medium containingHank's salts, and the mixture was placed in a BIORAD electroporationapparatus. Electroporation was performed at 20 volts, following whichthe cells were plated in 96 well microtiter plates.

Mycophenolic acid selection was applied after 24 hours and drugresistant colonies were identified after 1-2 weeks. Resistant colonieswere expanded to stable cell lines and tissue culture supernatant fromthese cell lines was tested for antibody using an ELISA assay with goatanti-human IgG Fc antibody and goat anti-human H+L conjugated withalkaline phosphatase (obtained from Jackson Laboratories).

The chimeric A2 antibody was purified from tissue culture supernatant byProtein A-Sepharose chromatography. The supernatant was adjusted to 0.1MTris, 0.002M EDTA, pH 8.0 and loaded on a Protein A-Sepharose columnequilibrated in the same buffer. The IgG was eluted with 0.1M citrate,pH 3.5, inhibited or neutralized with 1M Tris, and dialyzed intophosphate buffered saline (PBS).

The purified chimeric antibody was evaluated for its binding andinhibiting and/or neutralizing activity.

EXAMPLE X Specificity of an Anti-TNF Chimeric Antibody

Since the antigen binding domain of cA2 was derived from murine A2,these mAbs would be expected to compete for the same binding site onTNF. Fixed concentrations of chimeric A2 and murine mAb A2 wereincubated with increasing concentrations of murine and chimeric A2competitor, respectively, in a 96-well microtiter plate coated withrhTNF (Dainippon, Osaka, Japan). Alkaline-phosphatase conjugatedanti-human immunoglobulin and anti-mouse immunoglobulin secondantibodies were used to detect the level of binding of chimeric andmurine A2, respectively. Cross-competition for TNF antigen was observedin this solid-phase ELISA format (FIG. 9). This finding is consistentwith the expected identical epitope specificity of cA2 and murine A2.

The affinity constant for binding of mouse mAb A2 and cA2 to rhTNFα wasdetermined by Scatchard analysis (see, for example, Scatchard, Ann. N.Y.Acad. Sci. 51:660 (1949)). The results are shown in FIG. 10. Thisanalysis involved measuring the direct binding of ¹²⁵I labelled cA2 toimmobilized rhTNFα in a 96-well plate. The antibodies were each labelledto a specific activity of about 9.7 μCi/μg by the iodogen method. Anaffinity constant (Ka) of 0.5×10⁹ liters/mole was calculated for themouse mAb A2. Unexpectedly, the chimeric A2 antibody had a higheraffinity, with a Ka of 1.8×10⁹ liters/mole. Thus, the chimeric anti-TNFαantibody of the present invention was shown to exhibit a significantlyhigher affinity of binding to human TNFα than did the parental murine A2mAb. This finding was surprising, since murine and chimeric antibodies,fragments and regions would be expected to have affinities that areequal to or less than that of the parent mAb.

Such high affinity anti-TNF antibodies, having affinities of binding toTNFα of at least 1×10⁸ M⁻¹, more preferably at least 1×10⁹ M⁻¹(expressed as Ka) are preferred for immunoassays which detect very lowlevels of TNF in biological fluids. In addition, anti-TNF antibodieshaving such high affinities are preferred for therapy of TNF-α-mediatedconditions or pathology states.

The specificity of cA2 for TNF was confirmed by testing forcross-neutralization of human lymphotoxin (TNF-β). Lymphotoxin sharessome sequence homology and certain biological activities, for example,tumor cell cytotoxicity, with TNF (Pennica, et al., Nature 312:724-729(1984)). Cultured human A673 cells were incubated with increasingconcentrations of human lymphotoxin (GENENTECH, San Francisco, Calif.)with or without 4 μg/ml chimeric A2 in the presence of 20 μg/mlcycloheximide at 39° C. overnight. Cell death was measured by vitalstaining with naphthol blue-black, as above. The results indicated thatcA2 was ineffective at inhibiting and/or neutralizing human lymphotoxin,confirming the TNFα-specificity of the chimeric antibody.

The ability of A2 or cA2 to react with TNF from different animal specieswas also evaluated. As mentioned earlier, there are multiple epitopes onhuman TNF to which inhibiting and/or neutralizing mAbs will bind(Moller, et al., infra). Human TNF has bioactivity in a wide range ofhost animal species. However, certain inhibiting and/or neutralizingepitopes on human TNF are conserved amongst different animal species andothers appear to be restricted to humans and chimpanzees.

Neutralization experiments utilized endotoxin-activated cellsupernatants from freshly isolated human, chimpanzee, rhesus andcynomolgus monkey, baboon, pig, dog, rabbit, or rat monocytes as the TNFsource. As discussed above, murine mAb A2 inhibited or neutralizedactivity of only human and chimpanzee TNF, and had no effect on TNFderived from other primates and lower animals. A2 also did not inhibitor neutralize the cytotoxic effect of recombinant mouse TNF.

Thus, the epitope recognized by A2 is one shared by human and chimpanzeeTNFα. Chimeric A2 was also tested in this manner for cross-reactivitywith monocyte-derived TNF from rat, rabbit, dog and pig, as well as withpurified recombinant mouse TNFα, and natural and recombinant human TNFα.Chimeric A2 only inhibited or neutralized natural and recombinant humanTNFα. Therefore, cA2 appears to share species specificity with murineA2.

EXAMPLE XI In Vitro Activity and Neutralization Efficacy of a ChimericAnti-TNF Antibody

Both the murine and chimeric anti-TNFα antibodies, A2 and cA2 weredetermined to have potent TNF-inhibiting and/or neutralizing activity.In the TNF cytotoxicity assay described above, murine A2, at aconcentration of about 125 ng/ml completely inhibited or neutralized thebiological activity of a 40 pg/ml challenge of rhTNFα. Two separatedeterminations of inhibiting and/or neutralizing potency, expressed asthe 50% Inhibitory Dose (ID50) were determined to be 15.9±1.01 and17.9±1.6 ng/ml (Mean±Std error). Thus the mAb A2 has an ID50 of about 17ng/ml.

In this same experimental system, three other murine anti-TNFαantibodies (termed TNF-1, TNF-2 and TNF-3) of comparable bindingaffinity to TNF were found to have ID50 values of 1-2 orders ofmagnitude greater, and thus were significantly less potent inneutralization than A2.

The ability of cA2 to inhibit or neutralize human TNFα bioactivity invitro was tested using the bioassay system described above. CulturedA673 cells were incubated with 40 pg/ml natural (Genzyme, Boston, Mass.)or recombinant (Suntory, Osaka, Japan) human TNF with or withoutantibody overnight as above, and cell death was measured by vitalstaining. As expected based upon the above results with the A2 mousemAb, cA2 also inhibited or neutralized both natural and rhTNF in adose-dependent manner in the cytotoxicity assay (FIG. 11). In this assayformat, levels of cA2 as low as 125 ng/ml completely abolished the toxicactivity of TNF. Upon repeated analysis, the cA2 exhibited greaterTNF-inhibiting and/or neutralizing activity than did the parent murineA2 mAb. Such inhibiting and/or neutralizing potency, at antibody levelsbelow 1 μg/ml, can easily be attained in the blood of a subject to whomthe antibody is administered. Accordingly, such highly potent inhibitingand/or neutralizing anti-TNF antibodies, in particular the chimericantibody, are preferred for therapeutic use in TNFα-mediated pathologiesor conditions.

As mentioned above, TNF induces cellular secretion of IL-6. Furthermore,there is evidence that IL-6 is involved in the pathophysiology ofsepsis, although the precise role of IL-6 in that syndrome is unclear(Fong, et al., J Exp Med 170:1627-1633 (1989); Starnes Jr., et al., JImmunol 145:4185-4191 (1990)). The ability of cA2 to inhibit orneutralize TNF-induced IL-6 secretion was evaluated using cultured humandiploid FS-4 fibroblasts. The results in Table 2 show that cA2 waseffective in blocking IL-6 secretion in cells that had been incubatedovernight with TNF. TNF-induced IL-6 secretion was not inhibited in theabsence of a mAb or in the presence of a control mAb specific for anirrelevant antigen.

TABLE 2 IN VITRO NEUTRALIZATION OF TNF-INDUCED IL-6 SECRETRION TNFConcentration (ng/ml) Antibody 0 0.3 1.5 7.5 None <0.20   1.36   2.002.56 Control mAb <0.20   1.60   1.96 2.16 cA2 <0.20 <9.20 <0.20 0.30Values represent mean concentrations of IL-6 of duplicate wells, inng/ml. RhTNF (Suntory, Osaka, Japan), with or without 4 μg/ml antibody,was added to cultures of FS-4 fibroblasts and after 18 h, thesupernatant was assayed for IL-6 using the QUANTIKINE Human IL-6Immunoassay (from R&D Systems, Minneapolis, MN). Control mAb = chimericmouse/human IgGl anti-platelet mAb (7E3).

The ability of TNF to activate procoagulant and adhesion moleculeactivities of endothelial cells (EC) is thought to be an importantcomponent of pathology pathophysiology. In particular, this can beassociated with the vascular damage, disseminated intravascularcoagulation, and severe hypotension that is associated with the sepsissyndrome. Therefore, the ability of cA2 to block TNF-induced activationof cultured human umbilical vein endothelial cells (HUVEC) wasevaluated. TNF stimulation of procoagulant activity was determined byexposing intact cultured HUVEC cells to TNF (with or without antibody)for 4 hours and analyzing a cell lysate in a human plasma clottingassay. The results in Table 3 show the expected upregulation by TNF ofHUVEC procoagulant activity (reflected by a decreased clotting time).Chimeric antibody cA2 effectively inhibited or neutralized this TNFactivity in a dose-dependent manner.

TABLE 3 IN VITRO NEUTRALIZATION OF TNF-INDUCED PROCOAGULANT ACTIVITY TNFConcentration (ng/ml) Antibody μg/ml 250 25 0 None — 64 ± 4* 63 ± 1  133± 13  Control Ab 10.00 74 ± 6  N.D. 178 ± 55  cA2 10.00 114 ± 5  185 ±61  141 ± 18  cA2  3.30 113 ± 2  147 ± 3  N.D. cA2  1.10 106 ± 1  145 ±8  N.D. A2  0.37 73 ± 17 153 ± 4  N.D. cA2  0.12 64 ± 1  118 ± 13 N.D. * Values represent mean plasma clotting time, in seconds (± S.D.).Clotting time was determined in normal human plasma after addition ofthe rhTNF (Dainippon, Osaka, Japan) with or without antibody-treatedHUVEC lysate and Ca⁺⁺ at 37° C. N.D. = Not done. Control Ab is achimeric mouse/human IgGl anti-CD4 antibody.

In addition to stimulating procoagulant activity, TNF also inducessurface expression of endothelial cell adhesion molecules such as ELAM-1and ICAM-1. The ability of cA2 to inhibit or neutralize this activity ofTNF was measured using an ELAM-1 specific detection radioimmunoassay.Cultured HUVEC were stimulated with 250 ng/ml rhTNF (Dainippon, Osaka,Japan) with or without antibody at 37° C. overnight in a 96-well plateformat. Surface expression of ELAM-1 was determined by sequentialaddition of a mouse anti-human ELAM-1 mAb and ¹²⁵I-labelled rabbitanti-mouse immunoglobulin second antibody directly to culture plates at4° C.

As shown in FIG. 12, TNF induced the expression of ELAM-1 on the surfaceof cultured HUVEC cells, and this activity was again effectively blockedin a dose-related manner by cA2.

Finally, TNF is known to stimulate mitogenic activity in culturedfibroblasts. Chimeric A2 inhibited or neutralized TNF-inducedmitogenesis of human diploid FS-4 fibroblasts cultures, confirming thepotent inhibiting and/or neutralizing capability of cA2 against a broadspectrum of in vitro TNF biological activities.

EXAMPLE XII Determination of Amino Acid Sequences (epitope) on HumanTNF-α Recognized by cA2 mAb

Reagents The following reagents are readily available from commercialsources. FMOC-L-Ala-OPfp, FMOC-L-Cys(Trt)-OPfp, FMOC-L-Asp(OtBu)-OPfp,FMOC-L-Glu(OtBu)-OPfp, FMOC-L-Phe-OPfp, FMOC-Gly-OPfp,FMOC-L-His(Boc)-OPfp, FMOC-L-Ile-OPfp, FMOC-L-Lys(Boc)-OPfp,FMOC-L-Leu-OPfp, FMOC-L-Asn-OPfp, FMOC-L-Pro-OPfp, FMOC-L-Gln-OPfp,FMOC-L-Arg(Mtr)-OPfp, FMOC-L-Ser(tBu)-ODhbt, FMOC-L-Thr(tBu)-ODhbt,FMOC-L-Val-OPfp, FMOC-L-Trp-OPfp, FMOC-L-Try(tBu)-OPfp, and1-hydroxybenotriazol (HOBT) were obtained from Cambridge ResearchBiochemicals. Piperidine and was obtained from Applied Biosystems, Inc.1-Methyl-2-Pyrrolidinone (NMP) was obtained from EM Science; Methanolfrom J T Baker; Acetic Anhydride from Applied Biosystems, Inc.,Trifluoroaccetic acid (TFA) from Applied Biosystems, Inc.;Diisopropylamne (DIEA), Triethylamine, Dithiothreitol (DTT) and Anisolefrom Aldrich and Hydrochloric Acid (HCl) from J T Baker.

Abbreviations: FMOC, 9-fluorenylmethoxycarbonyl; tBu t-butyl ether; OtB,t-butyl ester; Boc, t-butyloxycarbonyl; Mtr,4-methoxy-2,3,6-trimethylbenzenesulfonyl; Trt, trityl; OPfp,pentafluorophenylester; ODhbt. oxo-benzotriazone ster;

A chimeric antibody of the present invention, designated cA2, was usedto determine which portions of the TNF amino acid sequence were involvedin inhibitory binding by the antibody by epitope mapping, whereby theamino acid sequences of TNF-α recognized by cA2 have been identified.

The complete primary sequence of human TNFα, according to Pennica et al,Nature 312:724-729 (1984) is shown in FIG. 13 (SEQ ID NO:1). Overlappingdecapeptides beginning with every second amino acid and covering theentire amino acid sequence of human TNF-α were synthesized onpolyethylene pins using the method of Gysen (Gysen et al., Peptides:Chemistry and Biological, Proceedings of the Twelfth American PeptideSymposium, p. 519-523, Ed, G. R. Marshall, Escom, Leiden, 1988). Sets ofpeptide pins bearing free N-terminal amino groups and acetylatedN-terminal amino groups were individually prepared. Both sets of peptidepins were incubated in solutions containing the anti-TNF mAb cA2 todetermine the amino acid sequences that make up the cA2 epitope on humanTNF-α, as described below. FIG. 14A shows the results of binding to theoverlapping decapeptides that comprise the entire sequence of humanTNFα. The O.D. (optional density) correlates directly with the increaseddegree of cA2 binding. FIG. 14B shows the results of binding of cA2 tothe same set of peptide pins in the presence of human TNFα. Thiscompetitive binding study delineates peptides which can shownon-specific binding to cA2.

There are at least two non-contiguous peptide sequences of TNF-αrecognized by cA2. Using the conventional protein numbering systemwherein the N-terminal amino acid is number 1, the cA2 mAb recognizes anepitope composed at least in part of amino acids located within residues87-108 or both residues 59-80 and 87-108 of TNF (SEQ ID NO:1). FIG. 15presents these non-contiguous sequences within the TNF sequence.

Unexpectedly, the mAb cA2 blocks the action of TNF-α without binding tothe putative receptor binding locus, which can include one or more of,e.g., 11-13, 37-42, 49-57 or 155-157 of hTNFα (of SEQ ID NO:1).Preferred anti-TNF mAbs are those that inhibit this binding of humanTNF-α to its receptors by virtue of their ability to bind to one or moreof these peptide sequences. These antibodies can block the activity ofTNF by virtue of binding to the cA2 epitope, such binding demonstratedto inhibit TNF activity. The identification of those peptide sequencesrecognized by cA2 provides the information necessary to generateadditional MAbs with binding characteristics and therapeutic utilitythat parallel the embodiments of this application.

Peptide Pin Synthesis. Using an epitope mapping kit purchased fromCambridge Research Biochemicals, Inc. (CRB), dodecapeptidescorresponding to the entire sequence of human TNF-α were synthesized onpolyethylene pins.

A synthesis schedule was generated using the CRB epitope mappingsoftware. Prior to the first amino acid coupling, the pins weredeprotected with a 20% piperidine in NMP solution for 30 minutes at roomtemperature. After deprotected, the pins were washed with NMP for fiveminutes at room temperature, followed by three methanol washes.Following the wash steps, the pins were allowed to air dry for at least10 minutes.

The following procedure was performed for each coupling cycle:

1) The amino acid derivatives and the HOBT were weighted out accordingto the weights required in the synthesis schedule.

2) The HOBT was dissolved in the appropriate amount of NMP according tothe synthesis schedule.

3) The amino acid derivatives were dissolved in the recommended amountof HOBT solution and 150 microliters were pipeted into the appropriatewells as directed by the well position sheet of the synthesis schedule.

4) The blocks containing the pins were placed into the wells, and the“sandwich” units stored in plastic bags in a 30° C. water bath for 18hours.

5) The pins were removed from the wells and washed once (for 5 minutes)with NMP, three times (for two minutes) with methanol and air dried for10 minutes.

6) The pins were deprotected as described above and the procedurerepeated.

To acetylate the peptides on one block of pins, the peptide pins werewashed, deprotected and treated with 150 microliters of a solutioncontaining NMP; acetic anhydride:triethylamine (5:2:1) for 90 minutes at30° C., followed by the washing procedure outlined above. The second setof peptide pins was deprotected by not acetylated to give freeN-terminal amino groups.

The final deprotection of the peptides to remove the side chainprotecting groups was done using a mixture ofTFA:anisole:dithiothreitol, 95:2.5:2.5 (v/v/w) for four hours at ambienttemperature. After deprotection, the pins were air dried for 10 minutes,followed by a 15 minute sonication in a solution of 0.1% HCl inmethanol/distilled water (1:1). The pins dried over night and were thenready for testing. ELISA Assay for cA2 Binding to TNF-α Peptide PINs

Reagents: Disruption Buffer: Sodium dihydrogen phosphate (31.2 g, Sigmacat # S-0751 or equivalent) and sodium dodecylsulfate (20.0 g, Sigma cat# L-3771 or equivalent) were dissolved in 2.0 L of milliQ water. The pHwas adjusted to 7.2±0.1 with 50% w/w sodium hydroxide (VWR cat #VW6730-3 or equivalent).

Blocking Buffer: Sodium dihydrogen phosphate (0.39 g, Sigma cat #S-0751or equivalent) disodium hydrogen phosphate (1.07 g, Baker cat # 3828-1or equivalent) and sodium chloride (8.50 g, Baker cat # 3624-5 orequivalent were dissolved in 1.0 L of milliQ water. The pH was adjustedto 7.2±0.1 with 50% w/w sodium hydroxide (VWR cat VW6730-3 orequivalent). Chicken egg albumin (10.0 g, Sigma cat #A-5503 orequivalent) and bovine serum albumin (10.0 g, Sigma, cat #A-3294 orequivalent) were dissolved at room temperature with gentle stirring. Thesolution was filtered, and to the solution was added Tween 20 (2.0 ml,Sigma cat #P-13.79 or equivalent). The solution was stirred gently atroom temperature for 30 min, filtered and stored at 40°.

PBS/Tween 20: A 10×concentrate was prepared by dissolving sodiumdihydrogen phosphate (3.90 g, Sigma cat # S-0751 or equivalent),disodium hydrogen phosphate (10.70 g, Baker cat #3828-1 or equivalent)and sodium chloride (85.0 g, Baker cat #3624-5 or equivalent) in 1.0 Lof milliQ water. The pH was adjusted to 7.2±0.1 with 50% w/w sodiumhydroxide (VWR cat #VW 6730 or equivalent). To the solution was addedTween 20 (5.0 mL, Sigma cat #P-1379 or equivalent), and the mixturestirred gently. Just prior to use 100 mL of this solution was diluted to1.0 L with milliQ water.

Substrate solution: Substrate buffer was prepared by dissolving citricacid (4.20 g, Malinckrodt cat #0627 or equivalent) and disodium hydrogenphosphate (7.10 g, Baker cat #3828-1 or equivalent) in 1.0 L of milliQwater. The pH was adjusted to 5.00 with 50% w/w sodium hydroxide (VWRcat #VW6730-3 or equivalent). Immediately prior to use an OPD substratetablet (30 mg, Sigma cat #P-8412 or equivalent and 30% (v/v) hydrogenperoxide (40 μL, Sigma cat #P-1379 or equivalent) were added to thesubstrate buffer 25.0 mL). The solution was wrapped in foil and mixedthoroughly.

4 NH₂SO₄; Sulfuric acid (53 mL, EM Science cat #SX1244-5 or equivalent)was slowly added to MILLI-Q water (447 mL) and cooled to roomtemperature prior to use.

Equipment: Molecular Devices Model nu-max plate reader or equivalent.Scientific Products Model R4140 Oscillating table shaker and equivalent.BRANSON Model 5200 ultra-sonic bath or equivalent. FINNPIPETTE Model4172317 multichannel pipeter or equivalent. CORNING Model 25801 96 welldisposable polystyrene Elisa Plates.

Prior to use and after each subsequent use the peptide pins were cleanedusing the following procedure. Disruption buffer (2.0 L) was heated to60° and placed in an ultra-sonic bath in a fume hood. To the disruptionbuffer was added dithiolthreitol (2.5 g, Sigma cat #D-0632 orequivalent). The peptide pins were sonicated in this medium for 30 min,washed thoroughly with milliQ waster, suspended in a boiling ethanolbath for 2 min, and air-dried.

Blocking buffer (200 μL) was added to a 96 well disposable polystyreneElisa plate and the peptide pins suspended in the wells. The peptidepins and plate were incubated for 2 h at room temperature on anoscillating table shaker. The plates and peptide pins were washed withPBS/Tween 20 (four times). To each well was added a 20 μg/mlconcentration of cA2 antibody (diluted with blocking buffer, 175μL/well). TNF competition was done by incubation of TNFα (40 μg/ml) andcA2 (20 μg/ml) in BSA/ovalbumin/BBS for three hours at room temperature.The peptide pins were suspended in the plate and incubated at 4°overnight. The peptide pins and plate were washed with PBS/Tween 20(four times). To each well was added anti-human goat antibody conjugatedto horseradish peroxidase (diluted with blocking buffer to 1/2000, 175μL/well, Jackson IMMUNORESEARCH Labs). The peptide pins were suspendedin the plate, and incubated for 1 h at room temperature on a oscillatingtable shaker. The plates and peptide pins were washed with PBS/Tween 20(four times). To each well added freshly prepared substrate solution(150 μL/well), the peptide pins were suspended in the plate andincubated for 1 h at room temperature on an oscillating table shaker.The peptide pins were removed and to each well is added 4N H₂SO₄ (50μL). The plates were read in a Molecular Devices plate reader (490 nm,subtracting 650 nm as a blank), and the results are shown in FIGS. 14Aand 14B, as described above.

EXAMPLE XIII Production Mouse Anti-Human TNF mAb Using TNF PeptideFragments

Female BALB/c mice, as in Example I above, are injected subcutaneouslyand intraperitoneally (i.p.) with forty μg of purified E. coli-derivedrecombinant human TNF (rhTNF) fragments comprising anti-TNF epitopes ofat least 5 amino acids located within the non-contiguous sequence 59-80,87-108 or both residues 59-80 and 87-108 of TNF (of SEQ ID NO:1), aspresented above, emulsified with an equal volume of complete Freund'sadjuvant (obtained from Difco Laboratories) in 0.4 ml is into a mouse.One week later, a booster injection of 5 μg of these rhTNF fragments inincomplete Freund's adjuvant is given i.p. followed by four consecutivei.p. injections of 10 μg of TNF fragments including anti-TNF epitopesincluding amino acids from residues 59-80, 87-108 or both 59-80 and87-108 of hTNFα (of SEQ ID NO:1) without adjuvant. Eight weeks after thelast injection, the mouse is boosted i.p. with 10 μg of TNF.

Four days later, the mouse is sacrificed, the spleen is obtained and aspleen cell suspension is prepared. Spleen cells are fused with cells ofthe nonsecreting hybridoma, Sp2/0 (ATCC CRL1581), at a 4:1 ratio ofspleen cells to Sp2/0 cells, in the presence of 0.3 ml of 30%polyethylene glycol, PEG 1450. After incubation at 37° C. for 6 hours,the fused cells are distributed in 0.2 ml aliquots into 96-well platesat concentrations of 2×10⁴ SP2/0 cells per well. Feeder cells, in theform of 5×10⁴ normal BALB/c spleen cells, are added to each well.

The growth medium used consisted of RPMl-1640 medium, 10%heat-inactivated fetal bovine serum (FBS) (Hyclone), 0.1 mM MEMnonessential amino acids, 1 mM sodium pyruvate, 2 mM L-glutamine, 100U/ml penicillin, 100 μg/ml streptomycin (GIBCO Laboratories) and, forselection, hypoxanthine-aminopterin-thymidine (HAT) (BoehringerMannheim). A solid-phase radioimmunoassay (RIA) is employed forscreening supernatants for the presence of mabs specific for rhTNFαfragments including portions of residues 59-80, 87-108 or both 59-80 and87-108 of hTNFα (of SEQ ID NO:1). This assay is described in Example II,above. The background binding in this assay is about 500 cpm. Asupernatant is considered positive if it yielded binding of 2000 cpm orhigher.

Of the supernatants screened, one or more positive supernatants areroutinely identified by RIA. Of these positive supernatants, the highestbinding (as shown by the higher cpm values) are subcloned at limitingdilution on mouse feeder cells. Upon further analysis of thesupernatants in neutralization assays, routinely one or more antibodiesare found to have potent inhibiting and/or neutralizing activity. Thesepositive and inhibiting and/or neutralizing hybridoma-lines are thenselected and maintained in RPMl-1640 medium with 10% FBS (GIBCO), 0.1 mMnonessential amino acids, 1 mM sodium pyruvate, 2 mM L-glutamine, 100U/ml penicillin and 100 μg/ml streptomycin.

EXAMPLE XIV Production of Murine and Chimeric Antibodies, Fragments andRegions from TNF Peptides

Murine and chimeric antibodies, fragments and regions are obtained byconstruction of chimeric expression vectors encoding the mouse variableregion of antibodies obtained in Example XIII and human constantregions, as presented in Examples IV-IX above.

The resulting chimeric A2 antibody is purified from tissue culturesupernatant by Protein A-Sepharose chromatography. The supernatant isadjusted to 0.1M Tris, 0.002M EDTA, pH 8.0 and loaded on a ProteinA-Sepharose column equilibrated in the same buffer. The IgG is theneluted with 0.1M citrate, pH 3.5, neutralized with 1M Tris, and dialyzedinto phosphate buffered saline (PBS).

The purified murine and chimeric antibodies, fragments and regions areevaluated for its binding and inhibiting and/or neutralizing activity.

EXAMPLE XV In Vitro Activity and Neutralization Efficacy of a ChimericAnti-TNF Antibody

Both the murine and chimeric anti-TNFα antibodies of the presentinvention, as obtained according to Examples XIII and XIV, aredetermined to have potent TNF-inhibiting and/or neutralizing activity,as shown for example, in the TNF cytotoxicity assay described above,expressed as the 50% Inhibitory Dose (ID50).

In this same experimental system, three other murine anti-TNFαantibodies (termed TNF-1, TNF-2 and TNF-3) of comparable bindingaffinity to TNF are found to have ID50 values of 1-2 orders of magnitudegreater, and thus have significantly less potent in neutralization, thanboth the murine and chimeric anti-TNFα antibodies of the presentinvention.

The ability of both the murine and chimeric anti-TNFα antibodies of thepresent invention, as obtained according to Examples XIII and XIV, toinhibit or neutralize human TNFα bioactivity in vitro is tested usingthe bioassay system described above. Cultured cells producing the murineor chimeric anti-TNFα antibodies of the present invention, as obtainedaccording to Examples XIII and XIV, are incubated with 40 pg/ml natural(Genzyme, Boston, Mass.) or recombinant (Suntory, Osaka, Japan) humanTNF with or without antibody overnight as above, and cell death ismeasured by vital staining. As expected, both the murine and chimericanti-TNFα antibodies of the present invention, as obtained according toExamples XIII and XIV, inhibited or neutralized both natural and rhTNFin a dose-dependent manner in the cytotoxicity assay. Such inhibitingand/or neutralizing potency, at antibody levels below 1 μg/ml, caneasily be attained in the blood of a subject to whom the antibody isadministered. Accordingly, such highly potent inhibiting and/orneutralizing anti-TNF antibodies, in particular the chimeric antibody,are preferred for therapeutic use in TNFα-mediated pathologies orconditions.

The ability of cA2 to inhibit or neutralize TNF-induced IL-6 secretionis evaluated using cultured human diploid FS-4 fibroblasts. The resultsare expected to show that both murine and chimeric anti-TNFα antibodiesof the present invention, as obtained according to Examples XIII andXIV, are effective in blocking IL-6 secretion in cells that had beenincubated overnight with TNF. TNF-induced IL-6 secretion is notinhibited in the absence of a mAb or in the presence of a control mAbspecific for an irrelevant antigen.

The ability of TNF to activate procoagulant and adhesion moleculeactivities of endothelial cells (EC) is thought to be an importantcomponent of pathology pathophysiology. In particular, this can beassociated with the vascular damage, disseminated intravascularcoagulation, and severe hypotension that is associated with the sepsissyndrome. Therefore, the ability of both the murine and chimericanti-TNFα antibodies of the present invention, as obtained according toExamples XIII and XIV, to block TNF-induced activation of cultured humanumbilical vein endothelial cells (HUVEC) is evaluated. TNF stimulationof procoagulant activity is determined by exposing intact cultured HUVECcells to TNF (with or without antibody) for 4 hours and analyzing a celllysate in a human plasma clotting assay. The results are expected toshow the expected upregulation by TNF of HUVEC procoagulant activity(reflected by a decreased clotting time). Both the murine and chimericanti-TNFα antibodies of the present invention, as obtained according toExamples XIII and XIV, are expected to effectively inhibit or neutralizethis TNF activity in a dose-dependent manner.

In addition to stimulating procoagulant activity, TNF also inducessurface expression of endothelial cell adhesion molecules such as ELAM-1and ICAM-1. The ability of both the murine and chimeric anti-TNFαantibodies of the present invention, as obtained according to ExamplesXIII and XIV, are expected to inhibit or neutralize this activity of TNFis measured using an ELAM-1 specific detection radioimmunoassay.Cultured HUVEC are stimulated with 250 ng/ml rhTNF (Dainippon, Osaka,Japan) with or without antibody at 37° C. overnight in a 96-well plateformat. Surface expression of ELAM-1 is determined by sequentialaddition of a mouse anti-human ELAM-1 mAb and ¹²⁵I-labelled rabbitanti-mouse immunoglobulin second antibody directly to culture plates at4° C.

TNF is expected to induce the expression of ELAM-1 on the surface ofcultured HUVEC cells, and this activity is again expected to beeffectively blocked in a dose-related manner by both the murine andchimeric anti-TNFα antibodies of the present invention, as obtainedaccording to Examples XIII and XIV.

Finally, TNF is known to stimulate mitogenic activity in culturedfibroblasts. Both the murine and chimeric anti-TNFα antibodies of thepresent invention, as obtained according to Examples XIII and XIV, areexpected to inhibit or neutralize TNF-induced mitogenesis of humandiploid FS-4 fibroblasts cultures, confirming the potent inhibitingand/or neutralizing capability of both the murine and chimeric anti-TNFαantibodies of the present invention, as obtained according to ExamplesXIII and XIV against a broad spectrum of in vitro TNF biologicalactivities.

EXAMPLE XVI In Vivo Activity and Efficacy of cA2 Antibody

Evidence that the potent in vitro inhibiting and/or neutralizingcapability of cA2 is manifest in vivo was obtained. Earlier animalstudies showed that administration of TNF to experimental animals mimicsthe pathology state obtained with either Gram-negative bacterialinfection or direct endotoxin administration (Tracey, et al., 1986.infra; Tracey, et al., 1987, infra; Lehmann, et al., infra).

An in vivo model wherein lethal doses of human TNF are administered togalactosamine-sensitized mice (Lehmann, V. et al., infra) issubstantially modified for testing the capability of both the murine andchimeric anti-TNFα antibodies of the present invention, as obtainedaccording to Examples XIII and XIV above, to inhibit or neutralize TNFin vivo. An i.p. challenge with 5 μg (0.25 mg/kg) of rhTNF resulted in80-90 percent mortality in untreated control animals and in animalstreated i.v. 15-30 minutes later with either saline or 2 mg/kg controlantibody (a chimeric IgG1 derived from murine 7E3 anti-platelet mAb). Incontrast, treatment with both the murine and chimeric anti-TNFαantibodies of the present invention, as obtained according to ExamplesXIII and XIV, is expected to reduce mortality to 0-30 percent with 0.4mg/kg of antibody, and to 0-10 percent with 20 mg/kgs. These expectedresults indicate that both the murine and chimeric anti-TNFα antibodiesof the present invention, as obtained according to Examples XIII andXIV, are capable of inhibiting and/or neutralizing the biologicalactivity of TNF in vivo as well as in vitro.

TABLE 4 PREVENTION OF HUMAN TNF-INDUCED LETHALITY BY CHIMERIC A2 Outcome(Survivors/Total) Anitbody Experiment #1 Experiment #2 None 1/10 N.D.Control Ab, 2 mg/kg 2/10  1/10 cA2 (2 mg/kg) 9/10 10/10 (p = 0.0001) (p= 0.0055) cA2 (0.4 mg/kg) 7/10 10/10 (p = 0.0001) (p = 0.07) FemaleC3H/HeN mice were administered 5 μg rhTNF (Dainippon, Osaka, Japan) + 18mg galactosamine i.p. and antibody was administered 15-30 minutes lateri.v. Deaths were recorded 48 h post-challenge. Control MAb = chimericmouse/human IgGl anti-platelet MAb (7E3). N.D. = not done. p valuesrefer to comparison with the control Ab.

EXAMPLE XVII cA2 MAb Safety in Chimpanzees

The epitope specificity of A2 can be for an epitope which predominatesin humans and chimpanzees. Therefore, the chimpanzee was chosen as arelevant mammalian species to determine the toxicological potential andprovide safety information for cA2. Chimpanzees were dosed at levels of15 mg/kg for four to five consecutive days and 30 mg/kg once or forthree consecutive days. No adverse clinical signs, and no changesconsidered to be cA2 treatment related were observed in the monitoredparameters including routine hematology and blood chemistry. Thus, dosesof up to 30 mg/kg for three consecutive days were well tolerated inchimpanzees.

EXAMPLE XVIII Clinical Activity and Efficacy of cA2 Antibody

Chimeric IgG1 anti-human TNF MAb cA2 was administered to healthy malehuman volunteers as patients. One hour after receiving 4 ng/kg of an NIHreference endotoxin, the volunteers were administered either saline, asa control, or 0.01, 0.10 or 10 mg/kg of cA2 in a pharmaceuticallyacceptable form. TNF levels in serum were measured over time and werefound to show a dose dependent decrease in peak TNF levels with no TNFbeing detected in volunteers receiving a 10 mg/kg dose of cA2.Accordingly, therapy with an anti-TNF antibody of the present inventionis expected to inhibit TNF-mediated effects in humans.

Patients receiving endotoxin developed pronounced leukopenia thought tobe due to margination of white blood cells. As the white blood cellsbecome activated, they can attach to endothelial receptors withresultant endothelial damage. At doses of 1.0 to 10.0 mg/kg, thisleukopenia is prevented, whereas, at 0.01 and 0.1 mg/kg dosages, a dropin white cell count was observed. The drop was most pronounced among thepolymorph cell line. In all patients there was a subsequentleukocytosis, which was unchanged by treatment with anti-TNF anti-bodycA2. This blocking effect on white blood cell margination is expected torepresent a protective effect against the endothelial damage associatedwith TNF. It is expected in the art that this TNF-related endothelialdamage plays a significant role in the morbidity and mortalityassociated with sepsis, and it is therefore expected that the anti-TNFantibodies of the present invention will provide a protective effectagainst these damaging effects, as presented herein.

EXAMPLE XIX Treatment of Sepsis in Humans Using a Chimeric Anti-TNFAntibody

The chimeric anti-TNF MAb cA2 has been used in two phase I/II studies.In a phase I/II study in septic patients, 20 patients with the sepsissyndrome received a single dose of either 0.1, 1.0, 5.0 or 10 milligramsof cA2 per kilogram bodyweight. Another 60 patients received 100milligrams of HA-1A, a human anti-lipid A Mab currently under evaluationfor gram negative sepsis, followed with either placebo or 1.0, 5.0, or10 milligrams cA2 per kilogram bodyweight. The cA2 was administered as asingle, intravenous infusion over a 60 minute period. Clinicalassessment, vital signs, and laboratory parameters were measured before,during and periodically for 28 days after the infusion. In this study,cA2 was well tolerated. No adverse events were reported as “probably” or“definitely” related to cA2. All deaths were reported as “definitelynot” related to cA2.

Accordingly, human treatment of rheumatoid arthritis in human patientswas expected, and found, to provide a suitable treatment, as describedherein.

EXAMPLE XX CLINICAL TREATMENT OF RHEUMATOID ARTHRITIS BY A ANTI-TNFANTIBODY OR PEPTIDE OF THE PRESENT INVENTION

A Phase I open label study was conducted for methods and compositions ofthe present invention using a chimeric anti-TNF MAb for the treatment ofpatients with severe refractory rheumatoid arthritis. Nine patients wereenrolled in the study. The first five patients were treated withchimeric anti-TNF antibody (cA2), 10 mg/kg as a single dose infused overa period of two hours. These patients were subsequently retreated with asecond infusion of 10 mg/kg on day 14 of the study. The second group offive patients received an infusion of 5 mg/kg on the first day of thestudy. They were then treated with additional infusions of 5 mg/kg ondays 5, 9, and 13. Four of the planned five patients in this secondgroup have been treated to date. Preparation, Administration, andStorage of Test Material The chimeric monoclonal anti-TNF antibody wassupplied in single-use glass vials containing 20 mL with 100 mg ofanti-TNF (5 mg/mL). The anti-TNF antibody was stored at 2-8° C. Prior toinfusion, the antibody was withdrawn from the vials and filtered througha low-protein-binding 0.22 μm filter. This filtered antibody was thendiluted to a final volume of 300 mL with normal saline. The 300 mLantibody preparation was then infused via an in-line filter over aperiod of not less than two hours.

Prior to each repeat infusion of study medication a test dose of 0.1 mLof the infusion was diluted in 10 mL of normal saline and administeredby slow IV push over 5 minutes. The patient was observed for 15 minutesfor signs or symptoms of an immediate hypersensitivity reaction. If noreaction was observed in this time period, the full dose wasadministered as described above.

Administration Protocol

Group 1 (patients 1-5): a total of 2 infusions, on day 1 and day 15 ofthe trial; dosage 10 mg/kg on each occasion;

Group 2 (patients 6-9): a total of 4 infusions, on days 1, 5, 9 and 13of the trial; dosage 5 mg/kg on each occasion.

All infusions were administered iv over 2 hours in a total volume ofcA2+saline of 300 ml. Infusions subsequent to the first in any patientwere preceded by a small test dose administered as an iv push. Allpatients had at least three years of disease activity with rheumatoidarthritis. The patients ranged in age from 23 to 63. All patients hadfailed therapy with at least three different DMARD (Disease ModifyingAnti-Rheumatic Drug). Six of the nine patients had serum rheumatoidfactors, and all nine patients had erosions present on X-rays.

Clinical Monitoring

Patients were monitored during and for 24 hours after infusions forhemodynamic change, fever or other adverse events. Clinical andlaboratory monitoring for possible adverse events was undertaken on eachfollow-up assessment day. Clinical response parameters were performed atthe time-points as specified in the flow charts present in Table 9A andTable 9B. These evaluations were performed prior to receiving anyinfusions.

Clinical response studies will be comprised of the following parameters:

1. Number of tender joints and assessment of pain/tenderness

The following scoring will be used:

0=No pain/tenderness

1=Mild pain. The patient says it is tender upon questioning.

2=Moderate pain. The patient says it is tender and winces.

3=Severe pain. The patient says it is tender and winces and withdraws.

2. Number of swollen joints

Both tenderness and swelling will be evaluated for each jointseparately. MCP's, PIP's etc. will not be considered as one joint forthe evaluation.

3. Duration of morning stiffness (in minutes)

4. Grip strength

5. Visual analog pain scale (0-10 cm)

6. Patients and blinded evaluators will be asked to assess the clinicalresponse to the drug. Clinical response will be assessed using asubjective scoring system as follows:

5=Excellent response (best possible anticipated response)

4=Good response (less than best possible anticipated response)

3=Fair response (definite improvement but could be better)

2=No response (no effect)

1=Worsening (disease worse)

Measurement of index of disease activity is scored according to thefollowing Table 5.

TABLE 5 Clinical characteristics of patients 1-5 Concom- Eros- Previousitant Disease Rheu- ions/ Treatment Anti- Patient Age/ Duration mat.Nod- (DMARDs rheumatic Number Sex (years) Factor ules only) Theraphy 0148/F  7 +ve +ve/+ve *Sal,DP, **Pred Myo,Aur, 5 mg MTX, Aza, Chl. 02 63/F 7 −ve +ve/−ve Sal,Myo, Para 1-2 g DP. 03 59/M  3 +ve +ve/−ve Aur,Chl,Pred Myo,MTX, 10 mg Sal. Ind 225 mg 04 56/M 10 +ve +ve/−ve Myo,DP, PredAza,Sal. 12.5 mg Ibu 2 g, Para 1-2 g 05 28/F  3 +ve +ve/−ve Myo,Sal,Pred DP,Aza. 8 mg, Para 1-2 g Cod 16 mg *Sal = Sulphasalazine; DP =D-penicillamine; Myo = Myocrisin; Aur = auranofin; MTX = methotrexate;Aza = azathioprine; Chl = hydroxychloroquine. **Pred = prednisolone(dosage/day); Para = paracetamol; Ind = Indomethacin; Ibu-ibuprofen; Cod= codeine phosphate.

TABLE 5 Clinical characteristics of patients 1-5 Concom- Eros- Previousitant Disease Rheu- ions/ Treatment Anti- Patient Age/ Duration mat.Nod- (DMARDs rheumatic Number Sex (years) Factor ules only) Theraphy 0148/F  7 +ve +ve/+ve *Sal,DP, **Pred Myo,Aur, 5 mg MTX, Aza, Chl. 02 63/F 7 −ve +ve/−ve Sal,Myo, Para 1-2 g DP. 03 59/M  3 +ve +ve/−ve Aur,Chl,Pred Myo,MTX, 10 mg Sal. Ind 225 mg 04 56/M 10 +ve +ve/−ve Myo,DP, PredAza,Sal. 12.5 mg Ibu 2 g, Para 1-2 g 05 28/F  3 +ve +ve/−ve Myo,Sal,Pred DP,Aza. 8 mg, Para 1-2 g Cod 16 mg *Sal = Sulphasalazine; DP =D-penicillamine; Myo = Myocrisin; Aur = auranofin; MTX = methotrexate;Aza = azathioprine; Chl = hydroxychloroquine. **Pred = prednisolone(dosage/day); Para = paracetamol; Ind = Indomethacin; Ibu-ibuprofen; Cod= codeine phosphate.

TABLE 7 Disease activity at entry for patients 1-5 ESR Grip (mm/hrNumber Ritchie Strength normal CRP Patient Morning Pain SwollenArticular L/R ranges: (mg/l; IDA Stiffness (0-10 cm Joints Index (mm/Hg;F < 15; normal (range: Number (mins) on VAS) (0-28) (0-69) max 300) M <10) range: < 10) 1-4) 01 60 3.9 19 30 108/107 35 5 2.67 02 20 2.7 25 3167/66 18 14 2.0 03 90 4.9 14 16 230/238 48 44 2.5 04 30 6.9 17 12204/223 24 35 2.33 05 90 5.7 28 41 52/89 87 107 3.0

TABLE 7 Disease activity at entry for patients 1-5 ESR Grip (mm/hrNumber Ritchie Strength normal CRP Patient Morning Pain SwollenArticular L/R ranges: (mg/l; IDA Stiffness (0-10 cm Joints Index (mm/Hg;F < 15; normal (range: Number (mins) on VAS) (0-28) (0-69) max 300) M <10) range: < 10) 1-4) 01 60 3.9 19 30 108/107 35 5 2.67 02 20 2.7 25 3167/66 18 14 2.0 03 90 4.9 14 16 230/238 48 44 2.5 04 30 6.9 17 12204/223 24 35 2.33 05 90 5.7 28 41 52/89 87 107 3.0

All patients have tolerated the infusions of chimeric anti-CD4 and noserious adverse reactions have been observed. Specifically, no episodesof hemodynamic instability, fevers, or allergic reactions were observedin association with the infusions. Patients have not experienced anyinfections.

Although this is a non-blinded study, all patients experiencedimprovement in their clinical assessments of disease status, as well inbiochemical parameters of inflammation measured in their serum.

Clinical assessments, including the duration of early morning stiffness;the assessment of pain on a visual analogue scale; total count ofswollen joints; Ritchie articular index (a scaled score which assessesthe total number of tender joints and the degree of joint tenderness);and Index of Disease Activity (a scaled score which incorporates severalclinical and laboratory parameters), showed impressive improvementscompared to controls. These improvements were typically in the range ofan 80% drop from the baseline score; a degree of improvement which iswell beyond the amount of improvement that can be attributed to placeboresponse. In addition, the duration of these improvements was for six toeight weeks in most cases, a duration of response far longer than wouldbe anticipated from a placebo.

The improvements in clinical assessments were corroborated byimprovements in biochemical inflammatory parameters measured in serum.The patients showed rapid drops of serum C-reactive protein, usually inthe range of 80% from the baseline. Reductions in the erythrocytesedimentation rate, usually in the range of 40%, were also observed.Circulating soluble TNF receptors were also decreased following therapy.The durations of the biochemical responses were similar to the durationof the clinical responses.

Preliminary assessment of immune responses to the chimeric anti-TNFantibody has shown no antibody response in the first four patients.

In summary, the preliminary evaluation of the results of this Phase Itrial indicate that treatment of patients with advanced rheumatoidarthritis with anti-TNF MAb of the present invention is well toleratedand anti-TNF treatment is associated with rapid and marked improvementin clinical parameters of disease activity, including early morningstiffness, pain, and a number of tender and swollen joints; and isaccompanied by improvement of biochemical parameters of inflammation.

Although this was an open label study, the magnitude of the clinicalimprovements is well beyond the degree of improvement that would beanticipated from a placebo response, such that the present invention isshown to have significant clinical efficacy for treating rheumatoidarthritis.

TABLE 9A Flowchart for CHIMERIC ANTI-TNF STUDY C0168TRA Group I (10mg/kg at day 1 and day 14) Pre Scr Screening Wk d1 0 d2 Wk 1 Wk 2 d14 Wk3 Wk 4 Wk 6 Wk 8 Consent x Demography x Physical x x ExaminationPregnancy Test x Weight x x x x Vital Signs x  x* x x  x* x x x xAnti-TNF x x Infusion Labs, see Chart x  x′ x x  x′ x x x x Clinical x x x′ x x x x (Safety) Clinical x  x′ x  x′ x x x x (Response) Synovialbiopsy x  x7 Response x evaluation Screening Wk d1 0 d2 Wk 1 Wk 2 d14 Wk3 Wk 4 Wk 6 Wk 8 Hematology + x  x′ x  x′ x x x x ESR Biochemistry x  x′x  x′ x x x x Urinalysis  x′ x  x′ x x x x CRP + RF  x′ x  x′ x x x xSerum Cytokines  x′ x  x′ x x x x PBL x x x Pharmacokinetics  x#  x#  x$HACA response  x′ x  x′ x x x x x x* = vital signs will be obtainedprior to infusion, every 30 minutes during the infusion and every 30minutes for 2 hours after the infusion. x′ = Needs to be done prior tothe infusion. x# = Serum samples will be obtained prior to the infusionand at 1, 2, 4, 8, 12, and 24 hours after the end of the infusion. x$ =Serum samples will be obtained to the infusion and at 2 hours

TABLE 9B Flowchart for CHIMERIC ANTI-TNF STUDY C0168TRA Group II2 (mg/kgevery 4 days, 4 times total) Pre Scr Screening d1 wk d2 0 d5 + d9 1 d13wk 2 wk 3 wk 4 wk 6 wk 8 Consent x Demography x Physical x x examPregnancy x test Weight x x x x x x Vital x  x* x  x*  x*  x* x x x x xsigns Anti-TNF x x x x Infusion Labs, x  x′ x  x′  x′  x′ x x x x x xsee chart Clinical x  x′  x′  x′ x x x x x Safety Clinical x  x′  x′ x xx x x Response Synovial x  x7 Biopsy Response x Evaluation Hematology +x  x′  x′ x x x x x ESR Biochemistry x  x′  x′ x x x x x Urinalysis  x′ x′ x x x x x CRP + RF  x′  x′ x x x x x Cytokines  x′  x′ x x x x x PBLx x x x Pharmaco-  x#  x#  x$  x$  x$ kinetics HACA  x′  x′ x x x x xResponse x* = Vital signs will be obtained prior to infusion, every 30minutes during the infusion and every 30 minutes for 2 hours afterinfusion. x′ = Needs to be done prior to the infusion. x# = Serumsamples will be obtained to the infusion and at 1, 2, 4, 8, 12, and 24hours after the end of the infusion. x$ = Serum samples will be obtainedprior to the infusion and at 2 hours after the end of the infusion.

TABLE 10 Measurement of the index of disease activity (DA) Variables ofDisease Activity Ritc- Morn- hie ing Grip Artic- Stiff- Pain Strengthular Hemoglobin IDA ness (VAS, (mm- In- (g/dl) score (min) cm)* Hg) dexMale Female ESR 1   <10   0-2.4 >200    0 >14.1 >11.7  0-20 2 10-30 2.5-4.4 50-200 1-7  13-14   10.8-11.6 21-45 3 31-120 4.5-6.4 30-49  8-1710-12.9  8.4-10.7 46-80 4 >120 6.5-10    <30 >18  <9.9  <8.3 >81 *Painwas measured on a visual analog scale (VAS) 0-10 cm.

Conclusions (1)

Safety of anti-TNF in RA

Anti-TNF was safe and very well tolerated:

no hemodynamic, febrile or allergic episodes;

no infections;

no clinical adverse events;

a single laboratory adverse event only, probably unrelated to anti-TNF.

Conclusions (2)

Efficacy of anti-TNF in RA

Anti-TNF therapy resulted in:

rapid and marked improvements in EMS, pain and articular index in mostpatients;

slower but marked improvement in swollen joint score, maximal by 3-4weeks;

rapid and impressive falls in serum CRP, and a slower fall in ESR;

normalization of CRP and ESR in some patients;

rapid falls in serum C4d (a complement breakdown product) and IL-6 inpatients where these indices were elevated at entry.

Duration of clinical improvements variable, with rebound in somepatients at 6-8 weeks.

Accordingly, the present invention has been shown to have clinicalefficacy in human patients for treating TNF involved pathologies usingTNF MAbs of the present invention, such as for treating rheumatoidarthritis. Additionally, the human clinical use of TNF antibodies of thepresent invention in humans is also shown to correlate with in vitrodata and in vivo animal data for the use of anti-TNF antibodies of thepresent invention for treating TNF-related pathologies.

EXAMPLE XXI TREATMENT OF CROENIS DISEASE IN HUMANS USING ANTI-TNFαANTIBODIES

Case History SB.

This 16 year old patient has a history of Crohn's disease since age 12.She was suffering from diarrhoea, rectal blood loss, abdominal pain,fever and weight loss. She showed perianal lesions, severe colitis andirregularity of the terminal ileum. She was treated with prednisolone(systemic and local) and pentasa. This resulted in remission of thedisease, but she experienced extensive side effects of the treatment.She experienced severe exacerbations at age 12 and 12 yrs, 5 months,(Immuran™ added), 12 yrs, 9 months, 13 yrs, 5 months, and 14 yrs, 10months. She experienced severe side effects (growth retardation, morbusCushing, anemia, muscle weakness, delayed puberty, not able to visitschool).

At 15 yrs, 11 months, she was diagnosed with a mass in the right lowerquadrant. She had a stool frequency of 28 time per week (with as much as10 times per day unproductive attempts). The Crohn's index wad 311, thepediatric score 77.5. The sedimentation rate was elevated. Albumen andhemoglobin reduced. Before the first treatment the score was 291 andpediatric score was 60, and she would possibly have to loose her colon.She was infused on compassionate grounds with 10 mg/kg cA2, without anyside effects noticed. One week after treatment her sedimentation ratewas reduced from 66 to 32 mm. The Crohn's index was 163 and pediatricscore 30. She was reported to feel much better and the frequency of thestools was reduced greatly. Thee was apparently no more diarrhoea, butnormal faeces. On October 15th, before the second infusion she hadgained weight, had a sedimentation rate of 20 mm, an albumen of 46 h/l,Crohn's index 105, pediatric score 15. There seemed to be improvement onvideo endoscopy. A second infusion was performed at 16 yrs.

The patient was greatly improved after the second infusion. A endoscopyshowed only 3 active ulcers and scar tissue.

This is in contrast with her colon on admission when the thought wasthat her colon should be removed. This case history shows a dramaticimprovement of severe Crohn's disease upon treatment with cA2 anti-TNFantibody.

TABLE 11 CASE HISTORY SB 11 y, 8 m: physical Diarrhoea, rectal bloodloss, examination: abdominal pain, fever (40%) weight loss perianallesions sigmoidoscopy: severe colitis, probably M. Crohn enterolysis:irregularity terminal ileum Therapy: prednisolone 10 mg 3 dd. Pentasa250 mg 3 dd. enema (40 mg prednisone, 2 g 5 ASA) ml 1 dd. Result:remission, however: extensive side effects of prednisone and stuntinggrowth Action: prednisone 11 y, 11 m exacerbation same clinical pictureas 11 y, 8 m sigmoidoscopy: recurrence of colitis (grade IV) in last 60cm and anus. Therapy: prednisolone 40 mg 1 dd Pentasa 500 mg 3 dd enema1 dd Result: better 12 y, 5 m: severe exacerbation; despite intensivetreatment sigmoidoscopy: extensive perianal and sigmoidal lesions;active disease Therapy: continued + Immuran ™ 25 mg 1 dd Result: slightimprovement however still growth retardation, cushing, anaemia, muscleweakness. Action: prednisone 12 y, 9 m: exacerbation sigmoidoscopy:extensive (active) colitis, polyps Action: prednisone: 30 mg 1 dd,Immuran ™ 50 mg 1 dd, Pentasa 500 mg 3 dd, enema 2 dd Result: stillneeds enema's with prednisone and oral prednisone. delayed puberty,stunting growth 14 y, 10 m: severe exacerbation, weight loss, abdominalpain, fever. ileoscopy: active colitis (grade IV), perianal lesions.Terminal ileum normal. Result: No remission still fever, poor appetite,weight loss, diarrhea, not able to visit school Important Findings: 14y, 11 m: 151.9 cm; 34 kg T = 38° C., Abdominal mass in right lowerquadrant stool frequency 28 per week (however goes 10-15 times a day butmost often without success) ESR 55 mm; Hb 6.2 mmol/1 Ht 0, 29 1/1; alb.38.4 g/l Crohn's Dis. Act. Index: 311 Pediatric score: 77.5 14 y, 11.2m: 151, 8 cm: 34.6 kg (before 1st Crohn's Dis 291 infusion) Act Index:Pediatric score: 60 14 y, 11.4 m: 151, 8 cm: 34.6.kg ESR 32 mm; Hb 5.7mmol/l Crohn's Dis 163 Act Index: pediatric score: 30 15 y, 0 m 152,1cm: 34.8 kg (before 2nd Feels like she has infusion never felt before.Parents also very enthusiastic ESR 30 mm: Hb 6, 3 mol/l Ht 0, 32 11; Alb46 g/l Crohn Dis 105 Act Index: Pediatric Score: 15 Video- Improvementendoscopy:

No problems or side effects observed during and following infusion.

Accordingly, anti-TNF antibodies according to the present invention, asexemplified by cA2, are shown to provide successful treatment of TNFrelated pathologies, as exemplified by Crohn's disease, in humanpatients with no or little side effects.

EXAMPLE XXII TREATMENT OF ARTHRITIS IN HUMANS USING CHIMERICIMMUNOGLOBULIN CHAIN OF THE PRESENT INVENTION

Patient Selection

Twenty patients were recruited, each of whom fulfilled the revisedAmerican Rheumatism Association criteria for the diagnosis of RA (Arnettet al., Arthritis Rheum. 31:315-324 (1988). The clinical characteristicsof the patients are shown in Table 12. The study group comprised 15females and 5 males, with a median age of 51 years (range 23-72), amedian disease duration of 10.5 years (range 3-20) and a history offailed therapy with standard disease-modifying anti-rheumatic drugs(DMARDs; median number of failed DMARDs: 4, range 2-7). Seventeen wereseropositive at entry or had been seropositive at some stage of theirdisease, all had erosions on X-Rays of hands or feet, and 3 hadrheumatoid nodules. All patients had active disease at trial entry, asdefined by an Index of Disease Activity (IDA; Mallya et al., Rheumatol.Rehab. 20:14-17 (1981) of at least 1.75, together with at least 3swollen joints, and were classed as anatomical and functional activitystage 2 or 3 (Steinbrocker et al., JAMA 140:659-662 (1949). The pooleddata for each of the clinical and laboratory indices of disease activityat the time of screening for the trial (up to 4 weeks prior to trialentry), and on the day of trial entry itself (week 0), are shown inTables 13 and 14.

TABLE 12 Demographic features of 20 patients with refractory rheumatoidarthritis. Disease Age/ Duration Previous Concomitant Patient Sex(years) DMARDs Therapy 1 48/F 7 SSZ, DP, GST, AU Pred 5 mg RMTX, AZA,HCQ 2 63/F 7 SSZ, GST, DP Para 1-2 g 3 59/M 3 AUR, HCQ, GST, Pred 10 mg,MTX, SSZ Indo 225 mg 4 56/M 10 GST, DP, AZA, SS Pred 12.5 mg, Z Ibu 2 g,Para 1-2 g 5 28/F 3 GST, SSZ, DP, AZ Pred 8 mg, A Para 1-2 g, Cod 16 mg6 40/M 3 SSZ, HCQ, AUR Nap 1 g 7 54/F 7 DP, GST, SSZ, AZ Para 1-2 g, AMTX Cod 16-32 mg 8 23/F 11 HCQ, GST, SSZ, Pred 7.5 mg, MTX AZA Dicl 100mg, Para 1-2 g, Dex 100-200 mg 9 51/F 15 GST, HCQ, DP, MT Pred 7.5 mg, XDicl 125 mg, Para 1-3 g 10 47/F 12 SSZ, CYC, MTX Ben 4 g 11 34/F 10 DP,SSZ, MTX Pred 10 mg, Para 1.5 g, Cod 30-90 mg 12 57/F 12 GST, MTX, DP,AU Asp 1.2 g R 13 51/F 7 SSZ, AZA Para 1-4 g 14 72/M 11 GST, DP, AZA, MTPred 5 mg, X Para 1-4 g, Cod 16-64 mg 15 51/F 17 HCQ, DP, SSZ, MT Asp0.3 g X 16 62/F 16 GST, DP, SSZ, MT Para 1-4 g, X AZA Cod 16-64 mg 1756/F 11 SSZ, DP, GST, MT Pred 7.5 mg, X HCQ, AZA Eto 600 mg, para 1-2 g,Dext 100-200 mg 18 48/F 14 GST, MTX, DP, SS Pred 7.5 mg, ZAUR, AZA Indo100 mg, Para 1-3 g 19 42/F 3 SSZ, MTX Fen 450 mg, Ben 6 g, Cod 30 mg 2047/M 20 GST, DP, SSZ, AZ Pred 10 mg, A Para 1-3 g *DMARDs = disease -modifying anti-rheumatic drugs SSZ = sulphasalazine; DP =D-penicillamine; GST = gold sodium thiomalate; AUR = auranofin; MTX =methotrexate; AZA = azathioprine; HCQ = (hydroxy) chloroquine; CYC =cyclophosphamide. Pred = prednisolone (dose/day); Para = paracetamol;Indo = Indomethacin; Ibu = ibuprofen; Cod = codeine phosphate; Nap =naprosyn; Dicl = diclofenac; # Dext = dextropropoxyphene; Ben =benorylate; Asp = asprin; eto = etodolac; Fen = fenbufen.

TABLE 13 Changes in clinical assessments following treatment ofrheumatoid arthritis patients with cA2. Grip Patient Pain Swollen GripStrength Assessment Morning Score Ritchie Joints Strength (R) (gradesWeek Stiffness (0-10) Index (0-28) (L) (0-300) (0-300) IDA improved ofTrial min cm (0-69) number mm Hg mm Hg (1-4) 0-3) Screen 135(0-600)7.4(4-9.7) 23(4-51) 16(4-28) 84(45-300) 96(57-300) 3(2.3-3.3) NA p value0 180(20-600) 7.1(2.7-9.7) 28(4-52) 18(3-27) 77(52-295) 92(50-293)3(2-3.5) NA p value 1 20(0-180) 2.6(0.6-7.8) 13(2-28) 13.5(1-25)122(66-300) 133(57-300) 2(1.5-3.3) 1(1-3) <0.001 <0.001<0.001; >0.05 >0.05 >0.05 <0.001 NA <0.002 p value 2 15(0-150)3.0(0.3-6.4) 13(1-28) 11.5(1-22) 139(75-300) 143(59-300) 2(1.5-3.2)1.5(1-3) <0.001 <0.001 <0.001 <0.003; <0.03; >0.05 <0.001 NA <0.02 >0.05p value 3 5(0-150) 2.2(0.2-7.4) 8(0-22) 6(1-19) 113(51-300) 142(65-300)2(1.2-3.2) 2(1-2) <0.001 <0.001 <0.001 <0.001; >0.05 >0.05 <0.001 NA<0.002 p value 4 15(0-90) 1.9(0.1-5.6) 10(0-17) 6(0-21) 124(79-300)148(64-300) 1.8(1.3-2.7) 2(1-2) <0.001 <0.001 <0.001 <0.001; <0.02;<0.03; <0.001 NA <0.002 >0.05 >0.05 p value 6 5(0-90) 1.9(0.1-6.2)6(0-18) 5(1-14) 119(68-300) 153(62-300) 1.7(1.3-2.8) 2(1-2) <0.001<0.001 <0.001 <0.001 <0.04; <0.05; <0.001 NA >0.05 >0.05 p value 815(0-60) 2.1(0.2-7.7) 8(1-28) 7(1-18) 117(69-300) 167(53-300)1.8(1.5-2.8) 2(1-3) <0.001 <0.001 <0.001 <0.001 <0.03; <0.03; <0.001NA >0.05 >0.05 Datas are expressed as the median (range) of values from20 patients; data from patient 15 were not included after week 2(dropout); P values show significance by Mann-Whitney test ccmpared withweek 0 values; adjusted for multiple statistical comparisons. IDA =Index of disease activity; NA = not applicable.

TABLE 13 Changes in clinical assessments following treatment ofrheumatoid arthritis patients with cA2. Grip Patient Pain Swollen GripStrength Assessment Morning Score Ritchie Joints Strength (R) (gradesWeek Stiffness (0-10) Index (0-28) (L) (0-300) (0-300) IDA improved ofTrial min cm (0-69) number mm Hg mm Hg (1-4) 0-3) Screen 135(0-600)7.4(4-9.7) 23(4-51) 16(4-28) 84(45-300) 96(57-300) 3(2.3-3.3) NA p value0 180(20-600) 7.1(2.7-9.7) 28(4-52) 18(3-27) 77(52-295) 92(50-293)3(2-3.5) NA p value 1 20(0-180) 2.6(0.6-7.8) 13(2-28) 13.5(1-25)122(66-300) 133(57-300) 2(1.5-3.3) 1(1-3) <0.001 <0.001<0.001; >0.05 >0.05 >0.05 <0.001 NA <0.002 p value 2 15(0-150)3.0(0.3-6.4) 13(1-28) 11.5(1-22) 139(75-300) 143(59-300) 2(1.5-3.2)1.5(1-3) <0.001 <0.001 <0.001 <0.003; <0.03; >0.05 <0.001 NA <0.02 >0.05p value 3 5(0-150) 2.2(0.2-7.4) 8(0-22) 6(1-19) 113(51-300) 142(65-300)2(1.2-3.2) 2(1-2) <0.001 <0.001 <0.001 <0.001; >0.05 >0.05 <0.001 NA<0.002 p value 4 15(0-90) 1.9(0.1-5.6) 10(0-17) 6(0-21) 124(79-300)148(64-300) 1.8(1.3-2.7) 2(1-2) <0.001 <0.001 <0.001 <0.001; <0.02;<0.03; <0.001 NA <0.002 >0.05 >0.05 p value 6 5(0-90) 1.9(0.1-6.2)6(0-18) 5(1-14) 119(68-300) 153(62-300) 1.7(1.3-2.8) 2(1-2) <0.001<0.001 <0.001 <0.001 <0.04; <0.05; <0.001 NA >0.05 >0.05 p value 815(0-60) 2.1(0.2-7.7) 8(1-28) 7(1-18) 117(69-300) 167(53-300)1.8(1.5-2.8) 2(1-3) <0.001 <0.001 <0.001 <0.001 <0.03; <0.03; <0.001NA >0.05 >0.05 Datas are expressed as the median (range) of values from20 patients; data from patient 15 were not included after week 2(dropout); P values show significance by Mann-Whitney test ccmpared withweek 0 values; adjusted for multiple statistical comparisons. IDA =Index of disease activity; NA = not applicable.

TABLE 16 260793 270793 280793 290793 020893 200893 270893 ESR-77 ESR-47BSR-58 ESR-77 ESR-77 ESR-46 ESR-38

All DMARDs were discontinued at least 1 month prior to trial entry.Patients were allowed to continue on a non-steroidal anti-inflammatorydrug and/or prednisolone (<12.5 mg/day) during the trial. The dosage ofthese agents was kept stable for 1 month prior to trial entry and duringthe course of the trial, and no parenteral corticosteroids were allowedduring these periods. Simple analgesics were allowed ad libitum.Patients with other serious medical conditions were excluded. Specificexclusions included serum creatinine>150 umol/liter (normal range 60-120umol/liter), hemoglobin (Hgb)<90 gm/liter (normal range 120-160 gm/liter[females]; 135-175 gm/liter [males]), white blood cell count(WBC)<4×10⁹/liter (normal range 4-11×10⁹/liter), plateletcount<100×10⁹/liter (normal range 150-400×10⁹/liter), and abnormal liverfunction tests or active pathology on chest X-Ray.

All patients gave their informed consent for the trial, and approval wasgranted by the local ethics committee.

Treatment

The cA2 antibody was stored at 4° C. in 20 ml vials containing 5 mg ofcA2 per milliliter of 0.01 M phosphate buffered saline in 0.15M sodiumchloride at a pH of 7.2 and was filtered through a 0.2 um sterile filterbefore use. The appropriate amount of cA2 was then diluted to a totalvolume of 300 ml in sterile saline and administered intravenously via a0.2 um in-line filter over a 2 hour period.

Patients were admitted to hospital for 9-24 hours for each treatment,and were mobile except during infusions. The trial was of an open,uncontrolled design, with a comparison of two treatment schedules.Patients 1 to 5 and 11 to 20 received a total of 2 infusions, each of 10mg/kg cA2, at entry to the study (week 0) and 14 days later (week 2).Patients 6 to 10 received 4 infusions of 5 mg/kg activity includedcomplete blood counts, C-reactive protein (CRP; by rate nephelometry)and the erythrocyte sedimentation rate (ESR; Westergren). Follow-upassessments were made at monthly intervals after the conclusion of theformal trial period, in order to assess the duration of response.

Analysis of improvement in individual patients was made using twoseparate indices. Firstly, an index of disease activity (IDA) wascalculated for each time point according to the method of Mallya andMace (Mallya et al., Rheumatol. Rehab. 20:14-17 (1981), with inputvariable of morning stiffness, pain score, Ritchie Index, grip strength,ESR and Hgb. The second index calculated was that of Paulus (Paulus etal., Arthritis Rheum. 33:477-484 (1990) which uses input variables ofmorning stiffness, ESR, joint pain/tenderness, joint swelling, patient'sand physician's global assessment of disease severity. In order tocalculate the presence or otherwise of a response according to thisindex, two approximations were made to accommodate our data. The 28swollen joint count used by us (nongraded; validated in Fuchs et al.,Arthritis Rheum. 32:531-537 (1989)) was used in place of the moreextensive graded count used by Paulus, and the patient's and physician'sglobal assessments of response recorded by us were approximated to theglobal assessments of disease activity used by Paulus infra. In additionto determining response according to these published indices, weselected 6 disease activity assessments of interest (morning stiffness,pain score, Ritchie index, swollen joint count, ESR and CRP) andcalculated their mean percentage improvement. We have used FIGS. 24 and25 to give an indication of the degree of improvement seen in respondingpatients.

Immunological Investigations—Rheumatoid factors were measured using therheumatoid arthritis particle agglutination assay (RAPA, FujiBerio Inc.,Tokyo, Japan), in which titers of {fraction (1/160)} or greater wereconsidered significant. Rheumatoid factor isotypes were measured byELISA (Cambridge Life Sciences, Ely, UK). The addition of cA2 atconcentrations of up to 200 ug/ml to these assay cA2, at entry, and days4, 8 and 12. The total dose received by the 2 patient groups wastherefore the same at 20 mg/kg.

Assessment

Safety Monitoring—Vital signs were recorded every 15 to 30 minutesduring infusions, and at intervals for up to 24 hours post infusion.Patients were questioned concerning possible adverse events before eachinfusion and at weeks 1, 2, 3, 4, 6, and 8 of the trial. A completephysical examination was performed at screening and week 8. In addition,patients were monitored by standard laboratory tests including completeblood count, C3 and C4 components of complement, IgG, IgM and IgA, serumelectrolytes, creatinine, urea, alkaline phosphatase, aspartatetransaminase and total bilirubin. Sample times for these tests werebetween 0800 and 0900 hours (pre-infusion) and 1200-1400 hours (24 hourspost completion of the infusion). Blood tests subsequent to 15 day 1were performed in the morning, usually between 0700 and 1200 hours.Urine analysis and culture were also performed at each assessment point.

Response Assessment—The patients were assessed for response to cA2 atweeks 1, 2, 3, 4, 6 and 8 of the trial. the assessments were all madebetween 0700 and 1300 hours by the same observer. The following clinicalassessments were made: duration of morning stiffness (minutes), paidscore (0 to 10 cm on a visual analog scale), Ritchie Articular Index(maximum 69; Ritchie et al., Quart. J. Med. 147:393-406 (1968)), numberof swollen joints (28 joint count; validated in Fuchs et al., ArthritisRheum. 32:531-537 (1989), grip strength (0 to 300 mm Hg, mean of 3measurements per hand by sphygmomanometer cuff) and an assessment offunction (the Stanford Health Assessment Questionnaire (HAG) modifiedfor British patients; 34). In addition, the patients' global assessmentsof response were recorded on a 5-point scale (worse, no response, fairresponse, good response, excellent response). Routine laboratoryindicators of disease systems did not alter assay results (data notshown). Antinuclear antibodies were detected by immunofluorescence onHEpo 2 cells (Biodiagnostics, Upton, Worcs. UK) and antibodies toextractable nuclear antigens were measured by counterimmunoelectrophoresis with poly-antigen extract (Biodiagnostics). Serapositive by immunofluorescence were also screened for antibodies to DNAby the Farr assay (Kodak Diagnostics, Amersham, UK). Anti-cardiolipinantibodies were measured by ELISA (Shield Diagnostics, Dundee,Scotland). Serum amyloid A (SAA) was measured by sandwich ELISA(Biosource International, Camarillo, Calif., USA). Antiglobulinresponses to the infused chimeric antibody were measured by an in-houseELISA, using cA2 as a capture reagent.

Cytokine Assays—Bioactive TNF was measured in sera using the WEHI 164clone 13 cytotoxicity assay (Espevik et al., J. Imm. Methods 95:99-105(1986). Total IL-6 was measured in sera using a commercial immunoassay(Medgenix Diagnostics, SA, Belgium) and by a sandwich ELISA developed‘in house’ using monoclonal antibodies provided by Dr. F. di Padova(Basel, Switzerland). Microtiter plates were coated with monoclonalantibody LNI 314-14 at a concentration of 3 ug/ml for 18 hours at 4° C.and blocked with 3% bovine serum albumin in 0.1M phosphate bufferedsaline, pH 7.2. Undiluted sera or standards (recombinant hIL-6, 0-8.1ug/ml) were added to the wells in duplicate and incubated for 18 hoursat 4° C. Bound IL-6 was detected by incubation with monoclonal antibodyLNI 110-14 for 90 minutes at 37° C., followed by biotin—labeled goatanti-murine IgG2b for 90 minutes at 37° C. (Southern Biotechnology,Birmingham, Ala.). The assay was developed using streptavidin—alkalinephosphatase (Southern Biotechnology) and p-nitrophenylphosphate as asubstrate and the optical density read at 405 nm.

Statistics—Comparisons between week 0 and subsequent time points weremade for each assessment using the Mann-Whitney test. For comparison ofrheumatoid factor (RAPA) titers, the data were expressed as dilutionsbefore applying the test.

This was an exploratory study, in which pre-judgements about the optimaltimes for assessment were not possible. Although it has not been commonpractice to adjust for multiple statistical comparisons in such studies,a conservative statistical approach would require adjustment of p valuesto take into account analysis at several time points. The p values havetherefore been presented in two forms: unadjusted, and after makingallowance for analysis at multiple time points by use of the Bonferroniadjustment. Where p values remained <0.001 after adjustment, a singlevalue only is given. A p value of <0.05 is considered significant.

Results

Safety of cA2—the administration of cA2 was exceptionally welltolerated, with no headache, fever, hemodynamic disturbance, allergy orother acute manifestation. No serious adverse events were recordedduring the 8-week trial. Two minor infective episodes were recorded,patient 15 presented at week 2 with clinical features of bronchitis andgrowth of normal commensals only on sputum culture. She had a history ofsmoking and of a similar illness 3 years previously. The illnessresponded promptly to treatment with amoxicillin, but her second cA2infusion was withheld and the data for this patient are therefore notanalyzed beyond week 2. Patient 18 showed significant bacteriuria onroutine culture at week 6(>10⁵/ml; lactose fermenting coliform), but wasasymptomatic. This condition also responded promptly to amoxicillin.

Routine analysis of blood samples showed no consistent adverse changesin hematological parameters, renal function, liver function, levels ofC3 or C4 or immunoglobulins during the 8 weeks of the trial. Four minor,isolated and potentially adverse laboratory disturbances were recorded.Patient 2 experienced a transient rise in blood urea, from 5.7mmol/liter to 9.2 mmol/liter (normal range 2.5 to 7 mmol/liter), with nochange in serum creatinine. This change was associated with thetemporary use of a diuretic, prescribed for a non-rheumatologicaldisorder. The abnormality normalized within 1 week and was classified as‘probably not’ related to cA2. Patient 6 experienced a transient fall inthe peripheral blood lymphocyte count, from 1.6 to 0.8×10⁹/liter (normalrange 1.0-4.8×10⁹/liter). This abnormality normalized by the next samplepoint (2 weeks later), was not associated with any clinicalmanifestations and was classified as ‘possible related’ to cA2. Patients10 and 18 developed elevated titers of anti-DNA antibodies at weeks 6and 8 of the trial, with elevated anti-cardiolipin antibodies beingdetected in patient 10 only. Both patients had a pre-existing positiveantinuclear antibody and patient 10 had a history of borderlinelymphocytopenia and high serum IgM. There were no clinical features ofsystemic lupus erythematosus and the laboratory changes were judged‘possibly related’ to cA2.

Efficacy of cA2

Disease Activity—The pattern of response for each of the clinicalassessments of disease activity and the derived IDA are shown in Table13. All clinical assessments showed improvement following treatment withcA2, with maximal responses from week 3. Morning stiffness fell from amedian of 180 minutes at entry to 5 minutes at week 6 (p<0.001,adjusted), representing an improvement of 73%. Similarly, the RitchieIndex improved from 28 to 6 at week 6, (p<0.001, adjusted, 79%improvement) and the swollen joint count fell from 18 to 5, (p<0.001,adjusted, 72% improvement). The individual swollen joint counts for alltime points are shown in FIG. 24. Grip strength also improved; themedian grip strength rose from 77 (left) and 92 (right) mm Hg at entryto 119 (left) and 153 (right) mmHg at week 6 (p<0.04, p<0.05, left andright respectively; p>0.05 after adjustment for multiple comparisons).The IDA showed a fall from a median of 3 at entry to 1.7 at week 6(p<0.001, adjusted). Patients were asked to grade their responses to cA2on a 5 point scale. No patient recorded a response of ‘worse’ or ‘nochange’ at any point in the trial. ‘fair’, ‘good’ and ‘excellent’responses were classed as improvements of 1, 2 and 3 gradesrespectively. At week 6, the study group showed a median of 2 grades ofimprovement (Table 13).

We also measured changes in the patients' functional capacity, using theHAQ modified for British patients (range 0-3). The median (range) HAQscore improved from 2(0.9-3) at entry to 1.1 (0-2.6) by week 6,(p<0.001; p<0.002 adjusted).

The changes in the laboratory tests which reflect disease activity areshown in Table 14. the most rapid and impressive changes were seen inserum CRP, which fell from a median of 39.5 mg/liter at entry to 8mg/liter by week 6 of the trial (p<0.001, adjusted; normal range<10mg/liter), representing an improvement of 80%. Of the 19 patients withelevated CRP at entry, 17 showed falls to the normal range at some pointduring the trial. The improvement in CRP was maintained in most patientsfor the assessment period (Table 14 and FIG. 25); the exceptions withhigh values at 4 and 6 weeks tended to be those with the higheststarting values (data not shown). The ESR also showed improvement, witha fall from 55 mm/hour at entry to 23 mm/hour at week 6 (p<0.03; p>0.05adjusted; 58% improvement; normal range<10 mm/hour, <15 mm/hour, malesand females respectively). SAA levels were elevated in all patients attrial entry, and fell from a median of 245 mg/ml to 58 mg/ml at week 1(p<0.003, adjusted; 76% improvement; normal range<10/mg/ml) and to 80mg/ml at week 2 (p<0.04, adjusted). No significant changes were seen inHgb, WBC or platelet count at week 6, although the latter did improve atweeks 2 and 3 compared with trial entry (Table 14).

The response data have also been analyzed for each individual patient.The majority of patients had their best overall responses at week 6, atwhich time 13 assessed their responses as ‘good’ while 6 assessed theirresponses as ‘fair’. Eighteen of the 19 patients who completed thetreatment schedule achieved an improvement in the index of DiseaseActivity (Mallya et al., Rheumatol. Rehab. 20:14-17 (1981) of 0.5 orgreater at week 6, and 10 achieved an improvement of 1.0 or greater. Allpatients achieved a response at week 6 according to the index of Paulus(Paulus et al., Arthritis Rheum. 33:477-484 (1990). Finally, allpatients showed a mean improvement at week 6 in the 6 selected measuresof disease activity (as presented above) of 30% or greater, with 18 ofthe 19 patients showing a mean improvement of 50% or greater.

Although the study was primarily designed to assess the short-termeffects of cA2 treatment, follow-up clinical and laboratory data areavailable for those patients followed for sufficient time (number=12).The duration of response in these patients, defined as the duration of a30% (or greater) mean improvement in the 6 selected disease activitymeasures, was variable, ranging from 8 to 25 (median 14) weeks.

Comparison of the clinical and laboratory data for patients treated with2 infusions of cA2 (each at 10 m/kg) compared with those treated with 4infusions (each at 5 mg/kg) showed no significant differences in therapidity or extent of response (data not shown).

Inununological Investigations and cytokines—Measurement of rheumatoidfactor by RAPA showed 14 patients with significant tiers (>{fraction(1/160)}) at trial entry. Of these, 6 patients showed a fall of at least2 titers on treatment with cA2, while the remaining patients showed achange of 1 titer or less. No patient showed a significant increase inRF titer during the trial. The median RF titer in the 11 patients fellfrom ½, 560 at entry to {fraction (1/480)} by week 8 (p>0.05; Table 14).Specific RF isotypes were measured by ELISA, and showed falls in the 6patients whose RAPA had declined significantly, as well as in some otherpatients. Median values for the three RF isotypes in the 14 patientsseropositive at trial entry were 119, 102 and 62 IU/ml (IgM, IgG and IgAisotypes respectively) and at week 8 were 81, 64 and 46 IU/ml (p>0.05).

We tested sera from the first 9 patients for the presence of bioactiveTNF, using the WEHI 164 clone 13 cytotoxicity assay (Espevik et al., J.Imm. Methods 95:99-105 (1986). In 8 patients, serum sets spanning theentire trial period were tested, while for patient 9, one pre-trial, oneintermediate and the last available sample only were tested. The levelsof bioactive TNF were below the limit of sensitivity of the assay in thepresence of human serum (1 pg/ml). Since production of CRP and SAA arethought to be regulated in large part by IL-6, we also measured serumlevels of this cytokine, using 2 different assays which measure totalIL-6. In the Medgenix assay, IL-6 was significantly elevated in 17 ofthe 20 patients at entry. In this group, levels fell from 60 (18-500)pg/ml to 40 (0-230) pg/ml at week 1 (p>0.05; normal range<10 pg/ml) andto 32 (0-210) pg/ml at week 2 (p<0.005, p<0.01, adjusted). These resultswere supported by measurement of serum IL-6 in the first 16 patients ina separate ELISA developed in-house. IL-6 was detectable in 11 of the16, with median (range) levels falling from 210 (25-900) pg/ml at entryto 32 (0-1,700) pg/ml at week 1 (p<0.02, p<0.04, adjusted; normalrange<10 pg/ml) and to 44 (0-240) pg/ml at week 2 (p<0.02, p<0.03,adjusted).

We tested sera from the first 10 patients for the presence ofanti-globulin responses to the infused chimeric antibody, but none weredetected. In many patients however, cA2 was still detectable in serumsamples taken at week 8 and this can have interfered with the ELISA.

Discussion

This is the first report describing the use of anti-TNFα antibodies inhuman autoimmune disease. Many cytokines are produced in rheumatoidsynovium, but we chose to target specifically TNFα because of mountingevidence that it was a major molecular regulator in RA. The studyresults presented here support that view and allow three importantconclusions to be drawn.

First, treatment with cA2 was safe and the infusion procedure was welltolerated. Although fever, headache, chills and hemodynamic disturbancehave all been reported following treatment with anti CD4 or anti CDw52in RA, such features were absent in our patients. Also notable was theabsence of any allergic event despite repeated treatment with thechimeric antibody, although the interval between initial and repeatinfusions can have been too short to allow maximal expression of anyanti-globulin response. The continuing presence of circulating cA2 atthe conclusion of the trial amy have precluded detection of antiglobulinresponses, but also implied that any such responses were likely to be oflow titre and/or affinity. Although we recorded 2 infective episodesamongst the study group, these were minor and the clinical courses wereunremarkable. TNFα has been implicated in the control of listeria andother infections in mice (Havell et al., J. Immunol. 143:2894-2899(1989), but our limited experience does not suggest an increased risk ofinfections after TNFα blockade in man.

The second conclusion concerns the clinical efficacy of cA2. Thepatients we treated had long-standing, erosive, and for the most partseropositive disease, and had each failed therapy with several standardDMARDs. Despite this, the major clinical assessments of disease activityand outcome (morning stiffness, paid score, Ritchie index, swollen jointcount and HAQ score) showed statistically significant improvement, evenafter adjustment for multiple comparisons. All patients graded theirresponse as at least ‘fair’, with the majority grading it as ‘good’. Inaddition, all achieved a response according to the criteria of Paulusand showed a mean improvement of at least 30% in 6 selected diseaseactivity measures.

The improvements in clinical assessments following treatment with cA2appear to be at least as good as those reported following treatment ofsimilar patients with anti-leukocyte antibodies. The two therapeuticapproaches can already be distinguished, however, by their effects onthe acute phase response, since in several studies of anti-leukocyteantibodies, no consistent improvements in CRP or ESR were seen. Incontrast, treatment with cA2 resulted in significant falls in serum CRPand SAA, with normalization of values in many patients. The changes wererapid and marked, and in the case of CRP, sustained for the duration ofthe study (Table 14). The falls in ESR were less marked, achievingstatistical significance only when unadjusted (Table 14).

These results are consistent with current concepts that implicate TNFαin the regulation of hepatic acute phase protein synthesis, eitherdirectly, or by control of other, secondary, cytokines such as IL-6(Fong et al., J. Exp. Med. 170:1627-1633 (1989), Guerne et al., J. Clin.Invest. 83:585-592 (1989)). In order to investigate the mechanism ofcontrol of the acute phase response in our patients, we measured serumTNFα and IL-6 before and after cA2 treatment. Bioactive TNFα was notdetectable in baseline or subsequent sera. We used 2 different assaysfor IL-6, in view of previous reports of variability between differentimmunoassays in the measurement of cytokines in biological fluids(Roux-Lombard et al., Clin. Exp. Rheum. 10:515-520 (1992), and bothdemonstrated significant falls in serum IL-6 by week 2. These findingssupport the other objective laboratory changes induced by cA2, andprovide in vivo evidence that TNFα is a regulatory cytokine for IL-6 inthis disease. Amongst the other laboratory tests performed, rheumatoidfactors fell significantly in 6 patients.

Neutralization of TNFα can have a number of beneficial consequences,including a reduction in the local release of cytokines such as IL-6 andother inflammatory mediators and modulation of synovialendothelial/leukocyte interactions. cA2 can also bind directly tosynovial inflammatory cells expressing membrane TNFα, with subsequent insitu cell lysis.

The results obtained in this small series have important implications,both scientifically and clinically. At the scientific level, the abilityof the neutralizing antibody, cA2, to reduce acute phase proteinsynthesis, reduce the production of other cytokines such as IL-6, andsignificantly improve the clinical state demonstrates that it ispossible to interfere with the cytokine network in a useful mannerwithout untoward effects. Due to the many functions and overlappingeffects of cytokines such as IL-1 and TNFα, and the fact that cytokinesinduce the production of other cytokines and of themselves, there hadbeen some pessimism as to whether targeting a single cytokine in vivowould have any beneficial effect (Kingsley et al., Immunol. Today12:177-179 (1991), Trenthan, Curr. Opin. Rheumatol. 3:369-372 (1991)).This view is clearly refuted. On the clinical side, the results ofshort-term treatment with cA2 are significant and confirm that TNFα isuseful as a new therapeutic target in RA.

EXAMPLE XXIII TREATMENT WITH CHIMERIC ANTI-TNF IN A PATIENT WITH SEVERULCERATIVE COLITIS

The patient is a 41 year old woman with long term ulcerative colitis,which was diagnosed by endoscopy and histology. She has a pancolitis,but the main disease activity was left-sided. There were noextra-intestinal complications in the past. Maintenance therapyconsisted of Asacol(TM). Only one sever flair-up occurred 4 yearspreviously and was successfully treated with steroids.

At beginning month one, she was admitted elsewhere because of a verysever flair-up of the ulcerative colitis. Treatment consisted of highdoses of steroids intravenously, antibiotics, asacol and Total ParentalNutrition. Her clinical condition worsened and a colectomy wasconsidered.

At end of month one, she was admitted at the internal ward of the AMC.Her main complaints consisted of abdominal pains, frequent water stoolswith blood and mucopus and malaise.

Medication: ASACOL 2 dd 500 mg, orally

Di-Adresone-T 1 dd 100 mg, intravenously

Flagyl 3 dd 500 mg, intravenously

Fortum 3 dd 1 gram, intravenously

Total parental nutrition via central venous catheter

On physical examination the patient was moderately ill with a weight of55 kg and a temperature of 36° C. Jugular venous pressure was notelevated. Blood pressure was 110/70 mm Hg with a pulse rate of 80 perminute. No lymphadenopathy was found. Oropharynx was normal. Centralvenous catheter was inserted in situ with no signs of inflammation atthe place of insertion. Normal auscultation of the lungs and heart. Theabdomen was slightly distended and tender. Bowel sounds where reduced.Liver and spleen where not enlarged. No signs of peritonitis. Rectalexamination was normal.

All cultures of the stools where negative.

Plain x-ray of the abdomen; slightly dilated colon. No thumb-printing,no free air, no toxic megacolon.

Sigmoidoscopy; (video-taped) Very severe inflammation with deep ulcers.Dilated rectum and sigmoid. Because of danger of perforation the color,the endoscopy was limited to the racto-sigmoid. No biopsies where taken.

Conclusion at time of admission: Severe steroid resistant flair-up ofulcerative colitis.

Antibiotics where stopped, because no improvement was noticed and therewas no temperature.

After informed consent of the patient, treatment was started with 10mg/kg bodyweight (a 550 mg) of cA2 chimeric monoclonal anti-TNF(Centocor) given intravenously over 2 hours (according the protocol ofcA2 used in severe Crohn's disease).

During the infusion there were no complaints. Vital signs were monitoredand were all normal. Before and after infusion blood samples wheredrawn. Two days after infusion she had less abdominal pain, the stoolfrequency decreased and no blood was seen in the stools any more.However she developed high temperature (40° C.). Bloodcultures wherepositive for Staphylococcus epidermidis. Infection of the central venouscatheter was suspected. The catheter was removed and the sameStaphylococcus was cultured from the tip of the central venous catheter.During this period she was treated with antibiotics for three days.After this her temperature dropped and she recovered substantially.Steroids were tapered off to 40 mg of prednisone daily.

After 14 days sigmoidoscopy was repeated and showed a remarkableimprovement of the mucosa with signs of re-epithelization. There were nosigns of bleeding, less mucous and even some normal vascular structureswere seen.

At four months she was discharged.

At the outpatient clinic further monitoring was done weekly. Patient isstill improving. Stool frequency is two times per day without blood ormucopus. Her laboratory improved, but there is still anaemia, probablydue to iron deficiency. A colonoscopy is planned in the nearby future.

Our conclusion is that this patient had a very severe flair-up of herulcerative colitis. She was refractory to treatment and a totalcolectomy was seriously considered. After infusion of cA2 the clinicalcourse improved dramatically in spite of the fact that there was acomplication of a sepsis which was caused by the central venouscatheter.

EXAMPLE XXIV p55 Fusion Protein Structure

The extracellular domains of the p55 and p75 receptors were expressed asIg fusion proteins from DNA constructs designed to closely mimic thestructure of naturally occurring, rearranged Ig genes. Thus, the fusedgenes included the promoter and leader peptide coding sequence of ahighly expressed chimeric mouse-human antibody (cM-T412, Looney et all,Hum. Antibody Hybridomas 1992, 3, 191-200) on the 5′ side of the TNFreceptor insert, and codons for eight amino acids of human J sequenceand a genomic fragment encoding all three constant domains of human IgG1on the 3′ side of the receptor insert position (FIGS. 27 and 28).

Minor changes were introduced at the N-terminal ends of the heavy chainfusion proteins so that the first two amino acids would be identical orsimilar to the first two amino acids (Gln-Ile) encoded by the cM-T412antibody gene (from which the leader peptide originated). This was doneto increase the likelihood that any interactions between the N-terminalend of the mature protein and the leader peptide would still result inefficient transport into the lumen of the endoplasmic reticulum. Boyd etal., Cell 1990, 62, 1031-1033. Therefore, the Asp¹ and Ser² residues ofnaturally-occurring p55 were replaced with a Gln residue, and the Leu¹residue of p75 was preceded by a Gln residue in all p75 constructs. Noamino acid changes were introduced at the N-terminal end of the p55light chain fusion.

Expression Vectors

PCR methodology was used to engineer cloned genes. Oligonucleotides werepurchased from National Biosciences (Plymouth, Minn.). PCR amplificationkits were from Perkin-Elmer (CA) and DNA sequencing kits from U.S.Biochemical Corporation (Cleveland, Ohio). Alkalinephosphatase-conjugated goat anti-human IgG was purchased from JacksonImmunoResearch (West Grove, Pa.). ¹²⁵I-labeled human TNF was obtainedfrom Du Pont Company, NEN (Boston, Mass.) and unlabeled recombinanthuman TNF from R&D Systems (Minneapolis, Minn.). Protein A-Sepharosebeads was purchased from PHARMACIA (Piscataway, N.J.).

PCR methodology was used to engineer two cloned genes encoding the heavychain or light chain of an efficiently expressed murine antibody,cM-T412 (see Looney et al.), for the purpose of directing the expressionof foreign genes in a mammalian cell system. The approaches were toeffectively delete the coding region of the antibody variable region andto place a unique restriction site in its place (StuI for the heavychain vector and EcoRV for the light chain vector).

The resulting vector contained 2.5 kb of 5′ flanking genomic DNA, thepromoter, the leader peptide coding sequence (including the leaderintron), a StuI cloning site to introduce inserts, coding sequence foreight amino acids of human J sequence Gly Thr Leu Val Thr Val Ser Ser(SEQ ID NO:6) followed by genomic sequences for the human IgG1 constantregion. An analogous vector was made from the cM-T412 light chain geneexcept that an EcoRV cloning site was introduced at the carboxylterminal end of the light chain leader peptide and a different human Jsequence was encoded by the vector Gly Thr Lys Leu Glu Ile Lys (SEQ IDNO:7). Both vectors are based on plasmid pSV2-gpt and subsequent vectorderivatives that contain genomic sequences for either the heavy chain orlight chain constant regions. See Mulligan et al., Science 209:1422-1427(1980). The E. coli gpt gene allows selection of transfected cells withmycophenolic acid.

Heavy Chain Vector A previously cloned EcoRI fragment containing thecM-T412 heavy chain gene (Goeddel et al., Cold Spring Harbor Symp.Quant. Biol. 1986, 51, 597-609) was subcloned into pUC19. Thisrecombinant plasmid was used as a template for two PCR reactions. In onereaction, an oligo corresponding to the “reverse” primer of the pUCplasmids and the 3′ oligo 5′-CCTGGATACCTGTGAAAAGA-3′ (SEQ ID NO:8) (boldmarks half of a Stul site; oligo was phosphorylated prior to the PCRreaction) were used to amplify a fragment containing 3 kb of 5′ flankingDNA, the promoter, transcription start site and leader peptide codingsequence (including the leader intron). In the second reaction, the 5′oligo 5′-CCTGGTACCTTAGTCACCGTCTCCTCA-3′ (SEQ ID NO:9) (bold marks halfof a Stul site; oligo phosphorylated prior to the PCR reaction) and anoligo corresponding to the “forward” primer of pUC plasmids amplified afragment encoding eight amino acids of human J sequence Gly Thr Leu ValThr Val Ser Ser (SEQ ID NO:6) and a splice donor to allow splicing tothe human constant region coding sequence provided in another vector.The two PCR fragments were digested with EcoRI and then simultaneouslyligated into EcoRI-digested pUC19 to make pHC684 (FIG. 27).

Because the Stul site formed at the junction of the two PCR fragmentswas followed by a ‘GG’ dinucleotide sequence, a dcm methylation site wasformed preventing Stul from digesting that site when the DNA was grownin HB101 strain of E coli. Therefore, the plasmid DNA was introducedinto dcm-JM110 E. coli cells and reisolated. Stul was then able to cutat the junction but a second Stul site in the 5′ flanking DNA was aapparent (DNA sequencing showed that Stul site to also he followed by aGG dinucleotide and therefore also methylated). To make the Stul cloningsite at the junction be unique, a 790 bp Xbal fragment that includedonly one of the two Stul sites was subcloned into pUC19 to make thevector pHC707 (FIG. 27A) which was then grown in JM110 cells. The Stulcloning site formed at the junction of the two PCR fragments second andthird nucleotides (i.e., ‘CA’) of the last codon (Ala) of the signalsequence in order to maintain the appropriate translation reading frame(FIG. 27).

A PCR fragment encoding a protein of interest can then be ligated intothe unique Stul site of pHC707. The insert can include a translationstop codon that would result in expression of a “non-fusion” protein.Alternatively, a fusion protein could be expressed by the absence of atranslation stop codon, thus allowing translation to proceed throughadditional coding sequences positioned downstream of the Stul cloningsite. Coding sequences in the Stul site of pHC707 would not be fuseddirectly to the IgG1 coding sequences in pHC730 but would be separatedby an intron sequence that partially originates from pHC707 andpartially from pHC730. These intron sequences would be deleted in thecell following transcription resulting in an RNA molecule that istranslated into a chimeric protein with the protein of interest fuseddirectly to the IgG1 constant domains.

The plasmid pHC730 was a modified form of an IgG1 expression, pSV2gpt-hCyl vector described previously (Goeddel et al., Cold Spring HarborSymp. Quant. Biol. 1986, 51, 597-609) (FIG. 28). The modifications were(1) removal of the unique Sal1 and Xbal sites upstream of the constantregion coding sequence, (2) insertion of a Sal1 linker into the uniqueBamHI site to allow use of Sal1 to linearize the plasmid prior totransfections, and (3) ligation into the unique EcoRI site the clonedcM-T412 EcoRI fragment but with the Xbal fragment flanking the V genedeleted (FIG. 29). The resulting expression vector had a unique Xbalsite for inserting the Xbal fragments from pHC707.

Light Chain Vector

A previously cloned HindIII fragment containing the cM-T412 light chaingene (Goeddel et al., Cold Spring Harbor Symp. Quant. Biol. 1986, 51,597-609) was subcloned into pUC19 and the resulting plasmid used astemplate for PCR reactions. In one PCR reaction the “reverse” pUC primerand the 3′ oligo 5′-AATAGATATCTCCTTCAACACCTGCAA-3′ (SEQ ID NO:10) (EcoRVsite is in bold) were used to amplify a 2.8 kb fragment containing 5′flanking DNA, the promoter, transcription start site and leader peptidecoding sequence (including the leader intron) of the cloned light chaingene. This fragment was then digested with HindIII and EcoRV. In asecond PCR reaction, the 5′ oligo 5′-ATCGGGACAAAGTTGGAAATA-3′ (SEQ IDNO:11) (bold marks half of an EcoRV site) and the “forward” pUC primerwere used to amplify a fragment encoding seven amino acids of human Jsequence (Gly Thr Lys Leu Glu Ile Lys) and an intron splice donorsequence. This fragment was digested with HindIII and ligated along withthe other PCR fragment into pUC cut with HindIII. The resulting plasmid,pLC671 (FIG. 29), has a unique EcoRV cloning site at the junction of thetwo PCR fragments with the EcoRV site positioned such that the firstthree nucleotides of the EcoRV site encoded the first amino acid of themature protein (Asp).

The pLC671 HindIII insert was designed to be positioned upstream ofcoding sequences for the human kappa light chain constant region presentin a previously described expression vector, pSV2gpt-hCk (FIG. 30).However, pSV2gpt-hCk contained an EcoRV site it its gpt gene. Because itwas desired that the EcoRV site in the pLC671 HindIII fragment be aunique cloning site after transferring the fragment into pSV2gpt-hCk,the EcoRV site in pSV2gpt-hCk was first destroyed by PCR mutagenesis.Advantage was taken of the uniqueness of this EcoRV site in pSV2gpt-hCkand a Kpn1 site 260 bp upstream of the EcoRV site. Therefore, the 260 bpKpn1-EcoRV fragment was removed from pSV2gpt-hCk and replaced with a PCRfragment that has identical DNA sequence to the 260 bp fragment exceptfor a single nucleotide change that destroys the EcoRV site. Thenucleotide change that was chosen was a T to a C in the third positionof the EcoRV recognition sequence (i.e., GATATC changed to GACATC).Because the translation reading frame is such that GAT is a codon andbecause both GAT and GAG codons encode an Asp residue, the nucleotidechange does not change the amino acid ended at that position.Specifically, pSV2gpt-hCk was used as template in a PCR reaction usingthe 5′ oligo 5′-GGCGGTCTGGTACCGG-3′ (SEQ ID NO:12) (Kpn1 site is inbold) and the 3′ oligo 5′-GTCAACAACATAGTCATCA-3′ (SEQ ID NO:13) (boldmarks the complement of the ASP codon). The 260 bp PCR fragment wastreated with the Klenow fragment of DNA polymerase to fill-in the DNAends completely and then digested with Kpn1. The fragment was ligatedinto pSV2gpt-hCk that had its Kpn1-EcoRV fragment removed to make pLC327(FIG. 30).

The HindIII fragment of pLC671 was cloned into the unique HindIII siteof pLC327 to make the light chain expression vector, pLC690 (FIG. 30).This plasmid can be introduced into cells without further modificationsto encode a truncated human kappa light chain, JCk, that contains thefirst two amino acids of the cM-T412 light chain gene, seven amino acidsof human J sequences, and the light chain constant region.Alternatively, coding sequence of interest can be introduced into theunique EcoRV site of pLC690 to make a light chain fusion protein.

TNF Receptor DNA Constructs

For the p55 heavy chain fusion, amino acids 3-159 of the p55extracellular domain were encoded in a PCR fragment generated using the5′ oligo 5′-CACAGGTGTGTCCCCAAGGAAAA-3′ (SEQ ID NO:14) (bold marks theVal³ codon) and the 3′ oligo 5′-AATCTGGGGTAGGCACAA-3′ (SEQ ID NO:15)(bold marks the complement of the Ile¹⁵⁹ codon). For the p55 light chainfusion, amino acids 2-159 were encoded in a PCR fragment made Using the5′ oligo 5′-AGTGTGTGTCCCCAAGG-3′ (SEQ ID NO:16) (bold marks the Ser²codon) and the same 3′ oligo shown above. The light chain vectorcontained the codon for Asp¹ of p55. The DNA template for these PCRreactions was a previously reported human p55 cDNA clone. Gray et al.,Proc. Natl. Acad. Sci. USA 1990, 87, 7380-7384.

A truncated light chain that lacked a variable region was expressed bytransfecting cells with the light chain vector with no insert in theEcoRV cloning site. The resulting protein, termed JC_(K), consisted ofthe first two amino acids of the cM-T412 light chain gene, seven aminoacids of human J sequence (Gly Thr Lys Leu Glu Ile Lys) (SEQ ID NO:7),and the human light chain constant region.

A non-fusion form of p55 (p55-nf) was expressed in CHO-K1 cells usingthe CMV-major immediate early promoter after introducing a translationstop codon immediately after Ile¹⁵⁹. Secreted p55 was purified byaffinity chromatography on a TNFα column.

Transfections and ELISA Assays

All plasmids were linearized with a restriction enzyme prior tointroducing them into cells. Cells of the myeloma cell line X63-Ag8.653were transfected with 12 μg of DNA by electroporation. Cell supernatantswere assayed for IgG domains. Briefly, supernatants were incubated inplates coated with anti-human IgG Fc and then bound protein detectedusing alkaline phosphatase-conjugated anti-human and light chains.

Purification of Fusion Proteins

Cell supernatants were clarified by centrifugation followed by passagethrough a 0.45 micron filter. Supernatants were adjusted to 20 mMTris-HCl, pH 8.3, 150 mM NaCl, and 1 mM EDTA (1×protein A buffer) andpassed over a column of protein A-Sepharose beads. The column was washedin 1×protein A buffer followed by 100 mM Na Citrate, pH 5.0 to elutebound bovine IgG originating from the cell media. Bound fusion proteinwas then eluted in 100 mM Na Citrate, pH 3.5, neutralized with 0.2volumes 1 M Tris, and dialyzed against PBS.

TNF Cytotoxicity Assays

TNF-sensitive WEHI-164 cells (Espevik et al., J. Immunol. Methods 1986,95, 99-105) were plated in 1 μg/ml actinomycin D at 50,000 cells perwell in 96-well microtiter plates for 3-4 hours. Cells were exposed to40 pM TNFα or TNFβ and varying concentrations of fusion protein. Themixture was incubated overnight at 37° C. Cell viability was determinedby adding 3-[4,5-dimethyl-thiazol-2-yl]-2, 5-diphenyltetrazolium bromidedye (MTT) to a final concentration of 0.5 mg/ml, incubating for 4 hoursat 37° C., lysing the cells in 0.1 N HCl, 0.1% SDS and measuring theoptical density at 550 nm wavelength.

Saturation Binding Analyses

Fusion proteins were captured while at a concentration of 10 ng/ml in96-well microtiter plates coated with goat anti-human Fc antibodies.Varying concentrations of ¹²⁵I-TNF (34.8 μCi/μg) were added in PBS/1%BSA and allowed to bind for two hours at room temperature. Plates werewashed and bound cpm determined. Non-specific binding was determinedusing an irrelevant antibody.

Several different versions of the p55 fusion proteins were expressed.Unlike what was reported for CD4 (Capon et al., Nature 1989, 337,525-531) and IL-2 (Landolfi, J. Biol. Chem. 1991, 146, 915-919) fusionproteins that also included the C_(H)1 domain of the heavy chain,inclusion of a light chain proved to be necessary to get secretion ofthe Ig heavy chain fusion proteins from the murine myeloma cells. Thelight chain variable region was deleted to enable the TNF R domain onthe heavy chain to bind TNF without stearic hindrance from the lightchain.

The “double fusion” (df) protein, p55-df2, has p55 fused to both theheavy chain and light chain and is therefore tetravalent with regard top55. p55-sf3 has the p55 receptor (and the same eight amino acids ofhuman J sequence present in p55-sf2 and p55-df2) linked to the hingeregion, i.e., the C_(H)1 domain of the constant region is deleted.

After one or two rounds of subcloning, spent cell supernatant from thevarious cell lines were yielding 20 μg/ml (for p55-sf2) of fusionprotein. The proteins were purified from the spent supernatant byprotein A column chromatography and analyzed by SDS-PAGE with or withouta reducing agent. Each fusion protein was clearly dimeric in that theirM_(r) estimates from their migration through a non-reducing gel wasapproximately double the estimated M_(r) from a reducing gel. However,two bands were seen for p55-sf2 and p55-df2. Two lines of evidenceindicated that, in each case, the lower bands did not include a lightchain while the upper bands did include a light chain. First, whenp55-sf2 containing both bands were passed over an anti-kappa column, theupper band bound to the column while the lower band passed through thecolumn. Second, Western blots have shown that only the upper bands werereactive with anti-kappa antibodies.

It is believed that the versions of these fusion proteins that do nothave a light chain (k) were not secreted to a significant degree butrather were primarily released from dead cells because 1) supernatantsfrom cells transfected with the p55 heavy chain fusion gene and no lightchain gene did not have detectable fusion protein until after there wassignificant cell death, and 2) the ratio of the k− to k+ versions ofp55-sf2 increased as cell cultures went from 95% viability to 10%viability.

WEHI Cytotoxicity Assays

The ability of the various fusion proteins to bind and neutralize humanTNFα or TNFβ was tested in a TNF-mediated cell killing assay. Overnightincubation of the murine fibrosarcoma cell line, WEHI 164 (Espevik etal., J. Immunol. Methods 1986, 95, 99-105), with 20 pM (1 ng/ml) TNFαresults in essentially complete death of the culture. When the fusionproteins were pre-incubated with TNFα (FIG. 31A) or TNFβ (FIG. 31B andTable 1 above) and the mixture added to cells, each fusion proteindemonstrated dose-dependent protection of the cells from TNFcytotoxicity. Comparison of the viability of control cells not exposedto TNF to cells incubated in both TNF and fusion protein showed that theprotection was essentially complete at higher concentrations of fusionprotein.

Tetravalent p55-df2 showed the greatest affinity for TNFα requiring aconcentration of only 55 pM to confer 50% inhibition of 39 pM (2 ng/ml)TNFα (FIG. 31A and Table 1). Bivalent p55-sf2 and p75P-sf2 were nearlyas efficient, requiring concentrations of 70 pM to half-inhibit TNFα.Approximately two times as much p75-sf2 was required to confer 50%inhibition compared to p55-sf2 at the TNF concentration that was used.The monomeric, non-fusion form of p55 was much less efficient atinhibiting TNFα requiring a 900-fold molar excess over TNFα to inhibitcytotoxicity by 50%. This much-reduced inhibition was also observed witha monomeric, Fab-like p55 fusion protein that was required at a2000-fold molar excess over TNFα to get 50% inhibition. The order ofdecreasing inhibitory activity was thereforep55-df2>p55-sf2=p75P-sf2>p75-sf2>>>monomeric p55.

EXAMPLE XXV p75

To make a p75 heavy chain fusion (p75-sf2), amino acids 1-235 (Smith etal., Science 1990, 248, 1019-1023 and Kohno et al., Proc. Natl. Acad.Sci. 1990, 87, 8331-8335) were encoded in a fragment prepared using the5′ oligo 5′-CACAGCTGCCCGCCCAGGTGGCAT-3′ (SEQ ID NO:17) (bold marks theLeu¹ codon) and the 3′ oligo 5′-GTCGCCAGTGCTCCCTT-3′ (SEQ ID NO:18)(bold marks the complement of the Asp²³⁵ codon). Two other p75 heavychain fusions (p75P-sf2 and p75P-sf3) were made using the same 5′ oligowith the 3′ oligo 5′-ATCGGACGTGGACGTGCAGA-3′ (SEQ ID NO:19). Theresulting PCR fragment encoded amino acids 1-182. The PCR fragments wereblunt-end ligated into the Stul or EcoRV site of the appropriate vectorand checked for the absence of errors by sequencing the insertscompletely.

Several different versions of the p75 fusion proteins were alsoexpressed. p75-sf2 has the complete extracellular domain of p75 fused tothe heavy chain while p75P-sf2 lacks the C-terminal 53 amino acids ofthe p75 extracellular domain. p75P-sf3 is the same as p75P-sf2 exceptthat it lacks the C_(H)1 domain. The region deleted in p75P-sf2 and -sf3contains sites of O-linked glycosylation and a proline-rich region,neither of which is present in the extracellular domain of p55.Seckinger et al., Proc. Nat. Acad. Sci. USA 1990, 87, 5188-5192.

Similar to p55-sf2, two bands were seen for p75-sf2 and p75P-sf2 (FIG.32B, lane 8).

Surprisingly, the order of decreasing inhibitory activity was differentfor TNFβ, as presented in FIG. 32. p75P-sf2 was most efficient atinhibition requiring a concentration of 31 pM to half-inhibit human TNFβat 2 pM. Compared to p75P-sf2, three times as much p75-sf2 and threetimes as much p55-sf2 were necessary to obtain the same degree ofinhibition. The order of decreasing inhibitory activity was thereforep75P-sf2>p75-sf2=p55-sf2.

Affinity Measurements

A comparison was made of the binding affinity of various fusion proteinsand TNFα by saturation binding (FIGS. 33A and 33B) and Scatchardanalysis (FIGS. 33C-H). A microtiter plate was coated with excess goatanti-Fc polyclonal antibody and incubated with 10 ng/ml of fusionprotein in TBST buffer (10 mM Tris-HCl, pH 7.8, 150 NaCl, 0.05%Tween-20) for 1 hour. Varying amounts of ¹²⁵I labeled TNFα (specificactivity—34.8 μCi/μg) was then incubated with the captured fusionprotein in PBS (10 mM Na Phosphate, pH 7.0, 150 mM NaCl) with 1% bovineserum albumin for 2 hours. Unbound TNFα was washed away with four washesin PBS and the cpm bound was quantitated using a y-counter. All sampleswere analyzed in triplicate. The slope of the lines in (FIGS. 33C-H)represent the affinity constant, K_(a). The dissociation constant(K_(d)) values (see Table 1) were derived using the equation K_(d)=1/K.

EXAMPLE XXVI In vivo Results

C3H mice were challenged with 5 μg of human TNFα after treatment with animmunoreceptor molecule of the invention. The effect of the treatmentwas compared with two control treatments. The first control, cA2, is achimeric mouse/human IgG₁ monoclonal antibody that binds human TNF, andthus is a positive control. The second control, c17-1A, is a chimericmouse/human IgG₁ irrelevant monoclonal antibody and is thus a negativecontrol. The results of the treatments were as presented in thefollowing Table 17.

TABLE 17 Treatment Dead Fraction % Dead 1 μg cA2 5/14 36% 10 μg CA2 1/157% 50 μg c17-1A 13/15  87% 1 μg p55-sf2 8/15 53% 10 μg p55-sf2 0/15 0%50 μg p55-sf2 0/15 0%

Mice were injected with 25 μg of p55 fusion protein or a controlantibody and 1 hour later were challenged with 1 μg lipopolysaccharide(type J5). Mice were checked 24 hours later. The results are presentedin the following Table 18.

TABLE 18 Treatment Dead Fraction % Dead Control Antibody 11/11 100%p55-sf2  0/13 0%

All references cited herein, including journal articles or abstracts,published or corresponding U.S. or foreign patent applications, issuedU.S. or foreign patents, or any other references, are entirelyincorporated by reference herein, including all data, tables, figures,and text presented in the cited references. Additionally, the entirecontents of the references cited within the references cited herein arealso entirely incorporated by reference.

Reference to known method steps, conventional methods steps, knownmethods or conventional methods is not in any way an admission that anyaspect, description or embodiment of the present invention is disclosed,taught or suggested in the relevant art.

The foregoing description of the specific embodiments will so fullyreveal the general nature of the invention that others can, by applyingknowledge within the skill of the art (including the contents of thereferences cited herein), readily modify and/or adapt for variousapplications such specific embodiments, without undue experimentation,without departing from the general concept of the present invention.Therefore, such adaptations and modifications are intended to be withinthe meaning and range of equivalents of the disclosed embodiments, basedon the teaching and guidance presented herein. It is to be understoodthat the phraseology or terminology herein is for the purpose ofdescription and not of limitation, such that the terminology orphraseology of the present specification is to be interpreted by theskilled artisan in light of the teachings and guidance presented herein,in combination with the knowledge of one of ordinary skill in the art.

19 157 amino acids amino acid linear peptide not provided 1 Val Arg SerSer Ser Arg Thr Pro Ser Asp Lys Pro Val Ala His Val 1 5 10 15 Val AlaAsn Pro Gln Ala Glu Gly Gln Leu Gln Trp Leu Asn Arg Arg 20 25 30 Ala AsnAla Leu Leu Ala Asn Gly Val Glu Leu Arg Asp Asn Gln Leu 35 40 45 Val ValPro Ser Glu Gly Leu Tyr Leu Ile Tyr Ser Gln Val Leu Phe 50 55 60 Lys GlyGln Gly Cys Pro Ser Thr His Val Leu Leu Thr His Thr Ile 65 70 75 80 SerArg Ile Ala Val Ser Tyr Gln Thr Lys Val Asn Leu Leu Ser Ala 85 90 95 IleLys Ser Pro Cys Gln Arg Glu Thr Pro Glu Gly Ala Glu Ala Lys 100 105 110Pro Trp Tyr Glu Pro Ile Tyr Leu Gly Gly Val Phe Gln Leu Glu Lys 115 120125 Gly Asp Arg Leu Ser Ala Glu Ile Asn Arg Pro Asp Tyr Leu Asp Phe 130135 140 Ala Glu Ser Gly Gln Val Tyr Phe Gly Ile Ile Ala Leu 145 150 155321 base pairs nucleic acid single linear cDNA not provided CDS 1..321 2GAC ATC TTG CTG ACT CAG TCT CCA GCC ATC CTG TCT GTG AGT CCA GGA 48 AspIle Leu Leu Thr Gln Ser Pro Ala Ile Leu Ser Val Ser Pro Gly 1 5 10 15GAA AGA GTC AGT TTC TCC TGC AGG GCC AGT CAG TTC GTT GGC TCA AGC 96 GluArg Val Ser Phe Ser Cys Arg Ala Ser Gln Phe Val Gly Ser Ser 20 25 30 ATCCAC TGG TAT CAG CAA AGA ACA AAT GGT TCT CCA AGG CTT CTC ATA 144 Ile HisTrp Tyr Gln Gln Arg Thr Asn Gly Ser Pro Arg Leu Leu Ile 35 40 45 AAG TATGCT TCT GAG TCT ATG TCT GGG ATC CCT TCC AGG TTT AGT GGC 192 Lys Tyr AlaSer Glu Ser Met Ser Gly Ile Pro Ser Arg Phe Ser Gly 50 55 60 AGT GGA TCAGGG ACA GAT TTT ACT CTT AGC ATC AAC ACT GTG GAG TCT 240 Ser Gly Ser GlyThr Asp Phe Thr Leu Ser Ile Asn Thr Val Glu Ser 65 70 75 80 GAA GAT ATTGCA GAT TAT TAC TGT CAA CAA AGT CAT AGC TGG CCA TTC 288 Glu Asp Ile AlaAsp Tyr Tyr Cys Gln Gln Ser His Ser Trp Pro Phe 85 90 95 ACG TTC GGC TCGGGG ACA AAT TTG GAA GTA AAA 321 Thr Phe Gly Ser Gly Thr Asn Leu Glu ValLys 100 105 107 amino acids amino acid linear protein not provided 3 AspIle Leu Leu Thr Gln Ser Pro Ala Ile Leu Ser Val Ser Pro Gly 1 5 10 15Glu Arg Val Ser Phe Ser Cys Arg Ala Ser Gln Phe Val Gly Ser Ser 20 25 30Ile His Trp Tyr Gln Gln Arg Thr Asn Gly Ser Pro Arg Leu Leu Ile 35 40 45Lys Tyr Ala Ser Glu Ser Met Ser Gly Ile Pro Ser Arg Phe Ser Gly 50 55 60Ser Gly Ser Gly Thr Asp Phe Thr Leu Ser Ile Asn Thr Val Glu Ser 65 70 7580 Glu Asp Ile Ala Asp Tyr Tyr Cys Gln Gln Ser His Ser Trp Pro Phe 85 9095 Thr Phe Gly Ser Gly Thr Asn Leu Glu Val Lys 100 105 357 base pairsnucleic acid single linear cDNA not provided CDS 1..357 4 GAA GTG AAGCTT GAG GAG TCT GGA GGA GGC TTG GTG CAA CCT GGA GGA 48 Glu Val Lys LeuGlu Glu Ser Gly Gly Gly Leu Val Gln Pro Gly Gly 1 5 10 15 TCC ATG AAACTC TCC TGT GTT GCC TCT GGA TTC ATT TTC AGT AAC CAC 96 Ser Met Lys LeuSer Cys Val Ala Ser Gly Phe Ile Phe Ser Asn His 20 25 30 TGG ATG AAC TGGGTC CGC CAG TCT CCA GAG AAG GGG CTT GAG TGG GTT 144 Trp Met Asn Trp ValArg Gln Ser Pro Glu Lys Gly Leu Glu Trp Val 35 40 45 GCT GAA ATT AGA TCAAAA TCT ATT AAT TCT GCA ACA CAT TAT GCG GAG 192 Ala Glu Ile Arg Ser LysSer Ile Asn Ser Ala Thr His Tyr Ala Glu 50 55 60 TCT GTG AAA GGG AGG TTCACC ATC TCA AGA GAT GAT TCC AAA AGT GCT 240 Ser Val Lys Gly Arg Phe ThrIle Ser Arg Asp Asp Ser Lys Ser Ala 65 70 75 80 GTC TAC CTG CAA ATG ACCGAC TTA AGA ACT GAA GAC ACT GGC GTT TAT 288 Val Tyr Leu Gln Met Thr AspLeu Arg Thr Glu Asp Thr Gly Val Tyr 85 90 95 TAC TGT TCC AGG AAT TAC TACGGT AGT ACC TAC GAC TAC TGG GGC CAA 336 Tyr Cys Ser Arg Asn Tyr Tyr GlySer Thr Tyr Asp Tyr Trp Gly Gln 100 105 110 GGC ACC ACT CTC ACA GTC TCC357 Gly Thr Thr Leu Thr Val Ser 115 119 amino acids amino acid linearprotein not provided 5 Glu Val Lys Leu Glu Glu Ser Gly Gly Gly Leu ValGln Pro Gly Gly 1 5 10 15 Ser Met Lys Leu Ser Cys Val Ala Ser Gly PheIle Phe Ser Asn His 20 25 30 Trp Met Asn Trp Val Arg Gln Ser Pro Glu LysGly Leu Glu Trp Val 35 40 45 Ala Glu Ile Arg Ser Lys Ser Ile Asn Ser AlaThr His Tyr Ala Glu 50 55 60 Ser Val Lys Gly Arg Phe Thr Ile Ser Arg AspAsp Ser Lys Ser Ala 65 70 75 80 Val Tyr Leu Gln Met Thr Asp Leu Arg ThrGlu Asp Thr Gly Val Tyr 85 90 95 Tyr Cys Ser Arg Asn Tyr Tyr Gly Ser ThrTyr Asp Tyr Trp Gly Gln 100 105 110 Gly Thr Thr Leu Thr Val Ser 115 8amino acids amino acid linear protein not provided 6 Gly Thr Leu Val ThrVal Ser Ser 1 5 7 amino acids amino acid linear protein not provided 7Gly Thr Lys Leu Glu Ile Lys 1 5 20 base pairs nucleic acid single linearcDNA not provided 8 CCTGGATACCTGTGAAAAGA 20 27 base pairs nucleic acidsingle linear cDNA not provided 9 CCTGGTACCTTAGTCACCGTCTCCTCA 27 27 basepairs nucleic acid single linear cDNA not provided 10AATAGATATCTCCTTCAACACCTGCAA 27 21 base pairs nucleic acid single linearcDNA not provided 11 ATCGGGACAAAGTTGGAAATA 21 16 base pairs nucleic acidsingle linear cDNA not provided 12 GGCGGTCTGGTACCGG 16 19 base pairsnucleic acid single linear cDNA not provided 13 GTCAACAACATAGTCATCA 1923 base pairs nucleic acid single linear cDNA not provided 14CACAGGTGTGTCCCCAAGGAAAA 23 18 base pairs nucleic acid single linear cDNAnot provided 15 AATCTGGGGTAGGCACAA 18 17 base pairs nucleic acid singlelinear cDNA not provided 16 AGTGTGTGTCCCCAAGG 17 24 base pairs nucleicacid single linear cDNA not provided 17 CACAGCTGCCCGCCCAGGTGGCAT 24 17base pairs nucleic acid single linear cDNA not provided 18GTCGCCAGTGCTCCCTT 17 20 base pairs nucleic acid single linear cDNA notprovided 19 ATCGGACGTGGACGTGCAGA 20

What is claimed is:
 1. A chimeric antibody comprising at least part of ahuman immunoglobulin constant region and at least part of a non-humanimmunoglobulin variable region, said antibody capable of binding anepitope specific for human tumor necrosis factor TNFα, wherein thenon-human immunoglobulin variable region comprises an amino acidsequence selected from the group consisting of SEQ ID NO: 3 and SEQ IDNO:
 5. 2. An immunoassay method for detecting human TNF in a sample,comprising: (a) contacting said sample with an antibody according toclaim 1, or a TNF binding fragment thereof, in detectably labeled form;and (b) detecting the binding of the antibody to said TNF.
 3. A chimericantibody comprising at least part of a human immunoglobulin constantregion and at least part of a non-human immunoglobulin variable region,said antibody capable of binding an epitope specific for human tumornecrosis factor TNFα, wherein the non-human immunoglobulin variableregion comprises a polypeptide encoded by a nucleic acid sequenceselected from the group consisting of SEQ ID NO: 2 and SEQ ID NO:
 4. 4.An immunoassay method for detecting human TNF in a sample, comprising:(a) contacting said sample with an antibody according to claim 3, or aTNF binding fragment thereof, in detectably labeled form; and (b)detecting the binding of the antibody to said TNF.
 5. A chimericantibody, comprising two light chains and two heavy chains, each of saidchains comprising at least part of a human immunoglobulin constantregion and at least part of a non-human immunoglobulin variable region,said variable region capable of binding an epitope of human tumornecrosis factor hTNFα, wherein said light chains comprise variableregions comprising SEQ ID NO: 3 and said heavy chains comprise variableregions comprising SEQ ID NO:
 5. 6. A chimeric antibody according toclaim 5, wherein the human immunoglobulin constant region is an IgG1. 7.A chimeric antibody comprising at least part of a human IgG1 constantregion and at least part of a non-human immunoglobulin variable region,said antibody capable of binding an epitope specific for human TNFα,wherein the non-human immunoglobulin variable region comprises apolypeptide encoded by a nucleic acid sequence selected from the groupconsisting of SEQ ID NO: 2 and SEQ ID NO:
 4. 8. A polypeptide comprisingthe amino acid sequence of SEQ ID NO: 3, wherein said polypeptide bindsto hTNFα and competitively inhibits the binding of monoclonal antibodycA2 to hTNFα.
 9. A polypeptide comprising the amino acid sequence of SEQID NO: 5, wherein said polypeptide binds to hTNFα and competitivelyinhibits the binding of monoclonal antibody cA2 to hTNFα.